Rilla Mill and Plushabridge circular walk
  1. Go through the gate and down the steps from the parking area. At the bottom, turn right and follow the woodland path. Keep right where the path forks and follow it to a gate across the path.

    In urban areas in cold countries such as Canada, a black form of the grey squirrel is more common which is able to withstand the cold better both by retaining more heat and also having a slower metabolism. In wilderness areas where predators are more common, the black squirrels don't seem to do so well, perhaps because they are less camouflaged against trees than the grey ones.

  2. Go through the gate and cross the stepping stones. Continue to reach a fork in the path with a pedestrian gate which you can just make out through the holly bush ahead.

    From Roman times, holly trees were planted near houses as it was believed to offer protection from witchcraft and lightning strikes. There is some scientific basis for the latter at least: the spines on the leaves can act as lightning conductors. The sharp points allow electrical charge to concentrate, increasing its potential to form a spark.

  3. Keep right and go through the gate behind the holly bush. Follow the path until it reaches a lane.

    A huge beech tree on the corner of the lane drops large numbers of beechnuts in the autumn.

    The fruit of the beech tree is known as "mast" or, less cryptically, "beechnuts" and these are not produced until the tree is 40-60 years old. The small triangular nuts are encased in spiky husks which split and drop from the trees from late August to early October. The kernels of these are edible and are similar to hazelnuts. They were once used as a source of flour, which was ground after the tannins had been leached out by soaking them in water. If you find them too bitter, you might want to try this trick, although toasting them in a hot pan is also a good option.

    Beech trees can live up to 400 years but the normal range is 150-250 years. Beech trees respond well to pruning and the lifetime of the tree is extended when the tree is pollarded. This was once a common practice and involves cutting all the stems back to a height of about 6ft during the winter when the tree is dormant. The 6ft starting point kept the fresh new growth out of the range of grazing animals. When allowed to grow to full size, a beech tree can reach 80ft tall with a trunk diameter of around 3ft.

  4. Turn right onto the lane and follow it to where a narrow lane departs to the left.

    Down the valley behind you along the lane, an open-cast mine known as Westcott Mine worked for lead and copper in the 1840s. The remains resemble quarries.

  5. Turn left onto the lane and follow it until it ends in a T-junction.

    The metallic minerals associated with outcrops of granite tend to occur in bands which radiate out from the granite outcrop. A band of tin deposits usually occurs closest to the granite, then beyond this a band containing copper ore. A band of zinc and lead deposits is commonly found further away from the granite, with just iron at the furthest extreme. The reason for the banding is that the deposition of each mineral occurs within a specific temperature range. Granite starts as a molten blob of magma which cools very slowly and provides a source of heat. The temperature of water in the cracks in the neighbouring rock therefore decreases with increasing distance from the hot granite.

  6. At the junction, turn left onto the lane and follow it until you reach a public footpath sign on the left beside a track.

    The settlement of Uphill was first recorded in 1302 spelt HuppeHull. The name is from mediaeval English and simply means "place on the hill".

  7. At the footpath sign, turn left down the track and follow it to a fork. Keep right at the fork between the granite gateposts for Colquite Cottage and follow the track to a bend where a waymarked path departs ahead.

    The track has an impressive display of bluebells in spring.

    In folklore, the bluebell is a symbol of constancy, presumably based on the fact that they flower in the same place every year. It was said that anyone who wears a bluebell is compelled to tell the truth. This could be the origin of the "…something blue…" that a bride should wear on her wedding day.

    Most waymarks you'll encounter are yellow, which is the convention for marking public footpaths, of which there are over 2000 miles in Cornwall. Permissive paths often use other colours such as black, white or green. Red and blue are reserved for byways and bridleways, respectively.

  8. Bear left to follow the path ahead and past a bypassed stile to a waymark. Turn right at the waymark and follow the steps to reach the river. Follow the path alongside the river, past a rope suspension bridge, until the path ends at a gate.

    Trees in the woodland include chestnut.

    The chestnut tree originated in Sardinia and there is evidence of its cultivation by humans from around 2000 BC. It was introduced into Britain by the Romans who planted chestnut trees on their campaigns to provide an easily stored and transported source of food for their troops.

  9. Go through the gate to reach a lane. Turn right and cross the bridge to reach a stile on the left. Cross the stile and follow the path along the river to reach an iron stile at the far end of the field.

    Starabridge is a 3-span clapper bridge (composed of pillars with slabs balanced between them) which is thought might originally date from the 16th Century, during the Tudor era. The east side of the bridge looks to have been damaged at some point in its history, and partially rebuilt, as part of the triangular cutwater is missing and the parapets are patched with brick.

  10. Climb the iron stile and cross the footbridge. Then walk along the edge of the meadow to reach a kissing gate.

    The River Lynher (pronounced "liner", as in ocean) is just over 20 miles long, rising on Bodmin Moor and joining the Tamar in its estuary near Saltash. The name dates back to mediaeval times, being recorded as "Lyner" in 1318. It is also known as the St Germans River at the point where it widens into a broad, tidal channel, close to its mouth.

    During Victorian times, the river was polluted by copper mining waste and during the late 20th century, runoff from intensive dairy farming and an increase in arable farming were found to be affecting water quality and silting the gravel beds needed by spawning salmon. In the early 21st century, a number of these issues were addressed under the Cornwall Rivers Project.

    The river is now a haven for wildlife with several stretches being designated as Sites of Special Scientific interest (SSSIs). The river's resident species include otters, brown trout and Atlantic salmon which breed in its major tributary, the Tiddy.

  11. Go through the gate and cross the stone footbridge over a small stream then continue alongside the main river to reach a wooden footbridge over another small stream.

    The stream joining the river beneath the stone footbridge drains the area around the Phoenix United Mine workings near Minions. Metals toxic to fish are often found dissolved in the water seeping from mines, so the metal levels in the main river and tributary streams are monitored.

  12. Cross the bridge and follow the path along the iron railings. Keep right along the path to climb away from the river and reach a lane.

    A salmon hatchery is run by volunteers on the River Lynher to offset the effects of salmon being caught commercially in nets at sea on the river's population.

    Salmon spawn in winter in the tributary streams of rivers, where the gravel is suitable. The young fish (known as "parr") grow by feeding on aquatic insects for one to three years. They then undergo a physiological preadaptation to life in seawater known as "smolting". In spring, large numbers of "smolts" swim downriver and migrate to the rich feeding grounds of the Norwegian Sea where they feed on fish such as herring and sandeels.

    Salmon exhibit a remarkable homing instinct, locating their river of origin using the earth's magnetic field and smell which includes pheromones released by other salmon in the river. Some salmon reach maturity after only one year at sea; these are known as "grise" and return in summer, weighing between 1 and 4kg. Larger fish, that take two or more years at sea to mature, usually return considerably earlier in the year.

    Salmon cease to feed on entering freshwater and having spawned, the fish (referred to as "kelts") are susceptible to disease and predators. However some do survive to repeat their epic journey again and there are records of some salmon spawning three times.

  13. Bear left onto the lane and follow it downhill to a junction.

    As you descend the hill, you pass through the hamlet of Measham which dates back to Mediaeval times. It was recorded around 1140 as "Meuuesham". The name is Anglo-Saxon, and the ham could either refer to a settlement or, equally likely in this case, the water meadow.

  14. Bear right across the road to the lane opposite with a Caradon Trail waymark post (next to a red post box set into the wall). Follow the lane past Lynher House on the left to reach a flight of steps next to a gate on the right, marked with a Public Footpath sign on the left.

    A short distance up the road to the right is where Cornish Yarg cheese used to be produced.

    Cornish Yarg is a soft cheese made from cows milk which varies in texture from creamy on the outside to crumbly towards the centre. The original version is wrapped in nettle leaves but it is now also available wrapped in wild garlic leaves. The name is the reverse of "Gray" as the cheese was originally made by a couple with this surname from Withiel, who discovered a recipe, thought to date from the 13th Century, in a dusty book in the attic. In the 1970s, the recipe was given to Lynher Dairies who now produce the cheese, still on a relatively small scale (from a single farm near Truro at the time of writing). Both versions of the cheese have won a number of British and International cheese awards. In order to comply with stringent US export standards, the US inspectors required an explanation of what stinging nettles were. We can assume that the introduction was gentler than it could have been, as the cheese is now on sale in the USA and growing in popularity.

  15. Follow the steps to the right to reach a stile. Cross the stile and follow the path up the steep bank to reach a gate at the top onto a lane.

    In spring, the white flowers of wood anemones can be seen to the right of the path.

    Wood anemones can be recognised by their white star-like flowers growing in shady locations during the spring. Hoverflies are important pollinators of the plant so you may also see these nearby. Avoid touching the plants as they are poisonous to humans and can cause severe skin irritation.

    The anemones grow from underground stems (rhizomes) and spread very slowly - to spread by six feet takes about 100 years! This makes it a good indicator of ancient woodland.

    It may be an urban myth that Eskimos have a large number of words for "snow" but it's cast iron fact that there are at least this many words for "hill" in Cornish:

    • Meneth was often used to refer to Cornwall's higher peaks, or (outside of Cornwall) to mountains.
    • Tor was used for hills with rock outcrops protruding (and for the rock outcrops themselves)
    • Brea was used to refer to the most prominent hill in a district.
    • Ryn refers to a "hill" in the sense of projecting ground, or a steep hill-side or slope.
    • Garth was used to refer to a long narrow hilltop.
    • Ambel refers to the side of a hill.
    • Mulvra refers to a round-topped hill.
    • Godolgh is a very small hill.
    • Bron means "breast" as well as hill.
  16. Go through the gate, turn left onto the lane and pass the cottage to reach a flight of steps on the right marked with a Public Footpath sign. Climb the steps to a stile, cross this and go through the gate into a field. Cross the field to the gate in the opposite hedge.

    If there are sheep in the field and you have a dog, make sure it's securely on its lead (sheep are prone to panic and injuring themselves even if a dog is just being inquisitive). If the sheep start bleating, this means they are scared and they are liable to panic.

    If there are pregnant sheep in the field, be particularly sensitive as a scare can cause a miscarriage. If there are sheep in the field with lambs, avoid approaching them closely, making loud noises or walking between a lamb and its mother, as you may provoke the mother to defend her young.

    Sheep may look cute but if provoked they can cause serious injury (hence the verb "to ram"). Generally, the best plan is to walk quietly along the hedges and they will move away or ignore you.

  17. Cross the stile beside the gate and head straight across the field to a kissing gate in the hedge opposite.

    The large hill directly ahead is Caradon Hill.

    Caradon Hill is the 6th highest hill in Cornwall with a 371 metre summit. The name is thought to originate from the Cornish word car for fort. The slopes are dotted with the remains of engine houses and the area was once famous for its copper mines, which were discovered relatively late in Cornwall's mining history. In an account documented in the early 20th Century, the area was described:

    On Saturday nights after pay-day, the populous villages of Caradon Town, Pensilva, Minions and Crows Nest were crowded with men, and resembled in character the mining camps of Colorado and the Far West.

    To the far right is Notter Tor and to the left of this, the Cheesewring quarry at Minions. The Cheesewring itself is also just visible, perched above the quarry face.

    The Cheesewring is a tor on Stowes Hill near Minions. The tor gets is name because it is topped with a natural rock formation that looks like the press with a stack of weights that was used to make cheese (and also cider as the apple pulp was known as "cheese"). The cheesewring was a well-known landscape feature by Tudor times and it featured in large illustrations in the margins of Cornwall maps at the end of this period. The granite slabs, which appear to have been balanced, were created by erosion over many thousands of years.

    More about the Cheesewring

  18. Go through the kissing gate and cross the field to an iron stile in the middle of the hedge ahead.

    Clover is a native plant and a member of the legume (pea and bean) family. It is also sown as a fodder crop and as "green manure" as it improves soil fertility. The two most common species are known simply as white clover and red clover, based on the colour of their flowers, with the latter generally being a slightly larger plant. Red clover leaves also have a white V shape.

  19. Cross the stile and cross the field to the corner diagonally opposite, approx 30m to the right of the gap in the hedge (if there's a crop in the field, you may need to follow around the right hedge). As you reach the corner, you'll see a waymarked gateway, tucked behind the hedge on the left.

    One of the nutrients that plants need are nitrates in order to make amino acids for building proteins. Plants in the pea family (also known as legumes) are able to manufacture their own nitrates from nitrogen in the atmosphere. The nitrates are later released into the soil when the leaves die and rot. The overall process of turning atmospheric nitrogen into nitrates in the soil is known as "nitrogen fixing" and this makes legumes useful in crop rotations to replenish nitrogen removed by other crops without resorting to chemical fertilisers. As well as peas and beans, clovers and vetches are also members of this family.

  20. Join the track and follow this to a gateway into a field on the left.

    From April to June, white flowers of Greater Stitchwort can be seen along hedgerows and paths. The petals are quite distinctive as each one is split almost all the way to create pairs - most of the flowers typically have 5 pairs.

    The hedgerows provide a good habitat for small birds such as members of the tit family.

    The name "tit" is thought to be from a Viking word for "small" and the tit family of birds were also known as the titmouse. This is nothing to do with mice but is from a Middle English word recorded in the 14th Century as titmose. This is thought to be based on Old English word for the tit family of birds - māse - which became mose in Middle English.

  21. Turn right, away from the field, and follow the track until it ends on a lane.

    Silverweed is a creeping plant which is fairly easily recognised by its silver-green toothed leaves. The silver colour is caused by hairs on the leaves. Yellow flowers with 5 petals appear in late June. It is said that the Romans used it as insoles for their shoes on long marches.

    Rosebay willowherb is a tall plant with a spike of pink flowers in late summer which can often be seen beside paths and tracks. Their long leaves have a distinctive thin, white vein along the centre.

    The name "rosebay" dates from at least Tudor times and is thought to be based on loose resemblances of the leaves to bay leaves and the flowers to wild roses. The overall family are also known as "willowherbs" due to the resemblance of the leaves to willow leaves. The two names have since been brought together resulting in the slightly confusing duplicate description of the leaf shape.

    Members of the tit family have been seen using tools such as a conifer needle to extract grubs from holes in trees and to exhibit social learning - once discovered, the behaviour of pecking through foil on milk bottle tops to reach the cream spread steadily across the country. This is quite impressive considering their brain weighs less than 1 gram.

  22. Turn left onto the lane and follow it to a track on the left beside Sutton Grange, marked with a public footpath sign opposite.

    The settlement of Sutton dates back to mediaeval times and was first recorded in 1175 when it was spelt "Sutun". The name is Anglo-Saxon: tun means "farm", so this was "South Farm".

  23. Turn left down the track and keep right to follow the lower track a short distance to reach a stile quite hidden in the bamboo on the right, roughly 5 metres before the track ends in a gate.

    Bamboo is a member of the grass family. Like grass, it can spread through underground stems. This combined with its dense growth makes it able to out-compete many other species. The largest species of bamboo can grow over 100ft tall!

  24. Cross the stile and bear left across the orchard to reach another stile. Cross this and step over the ditch to reach the track. Turn right onto the track and follow it downhill to an area beside a stream with metal fencing.

    Pineapple weed is related to chamomile and is consequently also known as false chamomile. Unlike chamomile, it doesn't have white flowers - its flowers consisting of little yellow balls are therefore quite distinctive. Even more so is the fruity pineapple-like scent when is trodden on or squeezed.

    Pineapple weed leaves and flowers can be eaten in salads or dried to make tea. The flower heads can also be used to make a syrup by first infusing the flower heads in simmering water then straining off the liquid and adding sugar to this.

    Buddleia are originally from northwest China and Japan where they grow in forest clearings, on riverbanks and on limestone outcrops where they are able to survive with minimal nutrients. They were introduced into the UK as an ornamental plant in the late 19th Century and can found in many gardens. Some have escaped and established a niche on industrial land which resembles their native limestone outcrops.

    The shrub is commonly known as the Butterfly Bush as the flowers are profuse, rich in nectar and are in the shape of champagne flutes; butterflies and bees have sufficiently long drinking apparatus to reach the bottom.

    The plant has two types of leaf; the broad green leaves are replaced with shorter hairy grey leaves during the winter which are more resistant to frost and the drying effect of cold winds.

    Genetic analysis has revealed that domestic apples originated from wild apples in Kazakstan near the Chinese border. It is thought that the apple was probably the first tree to be domesticated by humans, several thousand years ago. Wild apples grew in the British Isles in Neolithic times but domesticated apples were introduced by the Romans. Over 7500 varieties of apple are now known.

    The word "stile" is based on an Old English word stigel for ladder. This in turn came from an old Germanic word stig meaning "to climb" and the word "stair" also came from this.

    Conversely, the word "style" (now used for fashion etc. but originally for literary style or a writing tool i.e. stylus) is from French origins (naturally!). This came from an Old French word stile, derived from the Latin stilus. It's thought the "i" might have been changed to a "y" for snob value to be more like the (unrelated) Greek word stylos (for pillar).

  25. Bear left from the track to reach a section of wooden fence with a footpath sign beside a metal gate (next to the area of metal fencing). Go through the gate and follow the path to reach a stile onto a footbridge.

    The stream rises at Minions and collects water from the north side of Caradon Hill. It flows through Upton Cross to here and joins the river Lynher between Rilla Mill and Plushabridge, ultimately meeting the sea in Plymouth Sound.

    Rain falling on the far (west) side of Caradon Hill has a different destiny, forming the headwaters of the River Seaton which meets the sea near Looe Bay.

  26. Climb the stile (the top bar lifts) and cross the footbridge. In the field, turn left to follow parallel to the left hedge. As you approach the gateway, start heading uphill to reach a ladder stile roughly 30m to the right along the hedge from the gateway.

    The Ramblers Association and National Farmers Union suggest some "dos and don'ts" for walkers which we've collated with some info from the local Countryside Access Team.

    Do

    • Stop, look and listen on entering a field. Look out for any animals and watch how they are behaving, particularly bulls or cows with calves
    • Be prepared for farm animals to react to your presence, especially if you have a dog with you.
    • Try to avoid getting between cows and their calves.
    • Move quickly and quietly, and if possible walk around the herd.
    • Keep your dog close and under effective control on a lead around cows and sheep.
    • Remember to close gates behind you when walking through fields containing livestock.
    • If you and your dog feel threatened, work your way to the field boundary and quietly make your way to safety.
    • Report any dangerous incidents to the Cornwall Council Countryside Access Team - phone 0300 1234 202 for emergencies or for non-emergencies use the iWalk Cornwall app to report a footpath issue (via the menu next to the direction on the directions screen).

    Don't

    • If you are threatened by cattle, don't hang onto your dog: let it go to allow the dog to run to safety.
    • Don't put yourself at risk. Find another way around the cattle and rejoin the footpath as soon as possible.
    • Don't panic or run. Most cattle will stop before they reach you. If they follow, just walk on quietly.
  27. Cross the stile and bear right slightly up the bank to reach a gate in the middle of the far hedge.

    The Birdsfoot Trefoil has yellow flowers tinged with red that look like little slippers and appear in small clusters. They are followed by seed pods that look distinctly like bird's feet or claws. Common names referring to the flowers include "Butter and Eggs", "Eggs and Bacon" and "Hen and Chickens", and to the seed pods, the delightful "Granny's Toenails".

    It is a member of the pea family and is poisonous to humans (containing glycosides of cyanide) but not to grazing animals and can be grown as a fodder plant. It is the larval food plant of many butterflies and moths including the common blue and silver-studded blue, and an important nectar plant for many bumblebee species.

    Cows eat about 10kg of grass a day and a dairy cow produces around 50 pints a day on average rising to around 100 pints at their peak.

  28. Cross the ladder stile next to the gate and follow the left hedge to a waymarked farm gate.

    Many of the trees forming the hedge on the left are hawthorn.

    The flowers of the hawthorn are known as "May Blossom" and were traditionally used as decorations in May Day celebrations. Now, however, the hawthorn generally doesn't flower until the middle of May. The reason for this is that May has moved! Until 1752, Britain used the Julian Calendar which had leap years every 4 years but no other corrections. This results in a length of day that is fractionally too long, so the first of May gradually slipped forwards over the centuries. By the 1700s, the first of May was 11 days ahead of where it is today.

    In sheltered places, hawthorn trees can reach 20-40ft in height and live up to 400 years. In harsher environments such as the coast and moors they can be as little as 5-6ft tall.

  29. Go through the gate and follow the left hedge to a stile next to a gate.

    The large hill in the distance to the right is Kit Hill.

    Kit Hill Country Park, which includes the hill and surrounding area, was donated by the Duke of Cornwall to the Cornish people to mark the birth of Prince William in 1985. The hill was formed in the same way as Bodmin Moor by magma pushing up beneath the existing sedimentary rocks to form a body of granite and mineral veins in the cracks formed as the granite cooled. The name "kit" comes from the Old English word for a bird of prey, and the Country Park still has a population of buzzards and sparrowhawks.

  30. Cross the stile next to the gate and follow the left hedge to a gate onto a lane.

    Blackbirds begin singing from around the end of January but it is normally the overkeen young males initially - the older, wiser males wait until March, pacing themselves for the singing period which continues into the early summer. Blackbirds have been shown to sing more during and after rain but exactly why is not yet known.

  31. Go through the gate and bear left to where the lane ends at a junction. Turn left and follow the lane past a junction and over the bridge. Continue up the hill on the other side to a public footpath sign on the left.

    Plusha bridge was built in the late 15th Century to give miners in Caradon more convenient access to the parish church in Linkinhorne. Some of the elegance of the original three arch design has been lost when the bridge was widened for transport.

  32. Go through the metal gate through which the footpath sign points and a wooden pedestrian gate beyond this. Follow the path between the hedge and fence to a gate and stile.

    The common name "foxglove" dates back many hundreds of years but the origin is unknown. The "gloves" almost certainly refers to the shape of the flowers, and the Latin name Digitalis (finger-like) is along similar lines. The curious part is the "fox" and many different suggestions have been made as to where it came from. It is possible that it is a corruption of another word. One suggestion is "folks" which was once used to mean "fairies".

    Barbed wire was first used in Victorian times with several different people independently inventing and patenting different designs. Modern barbed wire is made from steel which is then galvanised to prevent it rusting (at least until the zinc coating dissolves away). The barbed wire used for fencing is often made of high-tensile (springy) steel which is suited to being laid in long, continuous lengths. As it is forbidden by the Highways Act of 1980 for barbed wire to block a Public Right of Way, one practical solution used by farmers is to put a plastic sheath over the barbed wire where it passes over a stile. In the rare circumstance that you encounter exposed barbed wire on a stile, the most likely cause for this is mischievous cattle pulling off the plastic sheaths; let the Countryside Team know and they can alert the landowner.

  33. Cross the stile next to the gate and follow the line of trees to a stile beneath the trees to the right of the farm gate.

    If you are crossing a field in which there are horses:

    • Do not approach horses if they have foals, make loud noises nor walk between a foal and its mother as you may provoke the mother to defend her young. Generally the best plan is to walk along the hedges.
    • Horses will often approach you as they are used to human contact. If horses approach you, do not run away as this will encourage them to chase you. If you are uncomfortable with their proximity, calmly walk away.
    • Do not feed the horses with sweets or otherwise. Some food which is harmless to humans can be deadly to horses.
    • If you have a dog, keep it under close control in a visible but safe place, and as still and quiet as possible.
  34. Cross the stile and pass to the right of the tree. Head across the middle of the field keeping to the right of the trees on the left side of the field to reach a metal gate next to a ladder stile in the far hedge.

    As well as being environmentally-friendly, wool fibre has a number of technical properties that synthetic fibres lack including fire-resistance and the ability to absorb and release moisture. Some novel high-tech uses are now being found for it including biodegradable ground cover matting to control soil erosion. As concerns grow over the effects of plastics in the environment and micro plastics turning up in all kinds of unwanted places (such as 80% of the human blood samples tested in a study), this may also lead to a renaissance in natural fibres including wool. It may therefore not be too long before demand increases and fields are once again full of neatly-shorn sheep.

  35. Go through the pedestrian section of the gate and turn left. Cross the footbridge and follow the path into a field. Follow the right hedge to the top of the field and down a grassy corridor to reach a gate at the far end.

    Wild arum lilies grow along the right-hand hedge near the top of the field.

    The wild arum (Arum Maculatum) is known by over 90 colourful folk names including "Lords and ladies", "Priest in the pulpit", "Devils and angels", "Cows and bulls" etc. Most of these have sexual connotations as the inflorescence (known as the "spadix") is obviously phallic, and is sheathed suggestively by the encircling, leaf-like spathe. Another name "Cuckoo Pint" alludes to the time of the flower's appearance being with the first cuckoos; "pint" stays on theme, being the Old English slang for penis (a contraction of "pintle").

    All members of the lily family, including wild arum, are poisonous to dogs.

    Solar panels work by a particle of sunlight (photon) knocking off a charged particle (electron) from one of the chemicals in the panel, leaving behind an oppositely-charged particle missing an electron. These freed electrons can be captured by an electrode and sent on a little journey before returning to the solar panel to fill in the holes where other electrons have been knocked off by sunlight. That little journey of the electrons is what we call "electricity".

  36. Go through the gate on the right and bear left onto the track. Follow this until it ends on a road.

    The effect of ivy on buildings is controversial as it depends a lot on the properties of the surface it adheres to. The rootlets wedge into any cracks in the surface and so on surfaces that are fragile, ivy will cause damage. A study for English Heritage found that on hard, firm surfaces, ivy did little damage. The blanket of leaves was also found to have beneficial insulating effects and protect the masonry from water, salt and pollution.

  37. Turn left onto the road and follow it downhill to a public footpath sign opposite The Manor House (pub).

    The name Rilla Mill was first recorded in 1441 spelt "Rillamylle" and is thought to take its name from the nearby manor of Rillaton. From the Domesday Book, Rillaton was formerly known as "Resleston" which is a mashup of the Cornish words res (ford) and lys (court, or simply, place) with a Saxon ending tun for "farm". The presence of a mill was mentioned in a document from 1161 and a surviving mill building was documented in the 19th and the early 20th Century, but was demolished in the 1960s when it was regarded as a hazard to road traffic. The mill leat and race are the only remaining parts.

  38. Turn right onto the footpath, signposted to Westcott. Follow the path to reach the flight of steps leading back to the car park.

    Yellow archangel is a native plant and member of the dead nettle family (and it's also known as the Golden Dead Nettle). The flowers are pale yellow, hence the first part of the name. The second part of the name (including the angelic association) is because it looks quite like a nettle but doesn't sting.

    Since the 1970s, a variegated garden variety of yellow archangel (sometimes known as "aluminium plant" due to silvery metallic areas on its leaves) has escaped into the wild where it is spreading rapidly, particularly in the Southwest. It can propagate from a small piece of creeping stem and also produces several hundred seeds. Once established, it forms dense carpets in shady areas which exclude other plants. It has been deemed so invasive that it is now illegal to introduced it into the wild.