Exmoor is situated on sedimentary rocks from the middle and lower Devonian period which was 410 – 360 million years ago. The lower Devonian period produced rocks such as sandstones and siltstones these are found along the coast to the east of Ilfracombe and stretch approximately 10 km inland. The middle Devonian rocks such as slates and limestones lie beneath the rest of Exmoor. These rocks were produced when mud or sand were deposited layer onto layer in the shallow waters of rivers, lakes or the sea. Over time these layers hardened into rocks and eventually were crushed between two crustal plates that were moving from the North and South. The pressure from these plates folded the rocks and formed a ridge and trough which runs from East to West. The sandstone that lies beneath most of Exmoor produces well drained soil, whilst areas that lie above the slates are wet, peaty and boggy.
In the centre of Exmoor there is a plateau which is now open moorland, to the north the erosion of the Bristol Channel has produced cliffs and an area that is defined as a Heritage coast. To the south of the plateau grass moorland is replaced by rounded hills mostly over 300m in height which are covered in heather. This area of high ground catches the clouds from the Atlantic and receives 2000mm of rain per year, which supplies the rivers and streams of Exmoor. These run quickly to the north and slower to the south. In the east of the park are the Brendon Hills, to the north these hills are wooded but in the south they are cultivated producing enclosed fields surrounded by beach hedges. This landscape reaches all across the south western slopes of the moor and supports some dairy farming whilst the rest of the farming on the moor is beef cattle and sheep.
IMPACTS OF TOURISM AND RECREATION.
The impact of tourism and recreation on Exmoor hasn’t been as great as it has been on other National Parks due to its location. Exmoor isn’t close to large towns or dense populations and as a result doesn’t attract the high numbers of visitors that other parks attract but still has problems due to over use. Certain areas attract large numbers of visitors and have been called honey spots such as Dunkery hill, Lynmouth and …… The most common problem faced by these places is that of erosion, this is produced by people walking, horse riding and cars. A good example of the problem is that of Drapers Way near to Wheddon cross, every year in spring the wooded valley produces a dense carpet of snow drops and attracts thousands of visitors over a short period of 2 or 3 weeks.
The only access to this area is a single track road which goes down a steep hill. Due to the fact this area is only popular for a couple of weeks there isn’t any parking and so the only place to park is on the grass verges, or in the passing points along the side of the road. As a result the roads towards this area quickly become blocked, the verges are destroyed gradually as cars try to pass each other or are parked on them and even the edges of the road surface begins to suffer damage. The footpaths begin to suffer from erosion as the high number of visitors pass over them especially as it’s a wet time of year. Riding is also a popular recreational activity on the moor especially at Dunkery Beacon which is the highest point on the moor. A horse’s hoof has 19 times the impact of a walker’s foot and so 1 horse has the same impact as 38 walkers. The paths at Dunkery Beacon can be used by as many as 100 horses per day which is the equivalent of 3800 walkers going over the paths every day. This type of erosion over a period of 5 years can change a 50cm path or sheep track into a 500cm wide gullied erosion scar.