This PAL contains the most complex ritual landscape on Dartmoor.
The remains of two of only a handful of Neolithic burial mounds on Dartmoor, known as long cairns, are to be found here, at Corringdon Ball and east Butterdon Hill These are the oldest known monuments on Dartmoor, the Neolithic period lasting from c. 4500BC to c. 2,300BC. Remains of the long mound of earth and stones, with vestiges of a stone chamber at one end can be seen.
The PAL also contains a remarkable number of stone rows, constructed around 4000 years ago, occupying the saddles between hill summits and the hill sides. There are five single rows, one double row and a complex of seven parallel rows. This latter, on the edge of Corringdon Ball, is unique. The stone row on Butterdon Hill is the second longest on Dartmoor with a length of about 2 km (1¼ miles); all the stone rows have burial sites (cairns) associated with them.
All the hill summits are occupied by large prehistoric round stone-built burial mounds (cairns) that command extensive views over much of the South Hams. From these locations other summit cairns can clearly be seen on the skyline. Further round cairns are often found clustered around the summit cairn or located in prominent locations nearby. The largest round cairn on Dartmoor is sited on the summit of Three Barrows. These highly visible and intervisible cairns are sometimes called prestige cairns and possibly served the dual function of burial place and territorial marker.
The relationship between these scattered ritual monuments, their relationship with each other and with the wider landscape remains to be determined; but this area obviously had enormous significance in prehistoric times.
Some prehistoric settlement is located along the West Glaze Brook and on Corringdon Ball and is believed to be about 3,500 years old. The turf-covered remains of stone built round houses (hut circles) are to be found in both open groups and within enclosures formed by dry stone walls.
The valley bed of the East Glaze Brook has been worked for tin ore, probably in medieval times. There is a remarkably regular pattern of parallel tin prospecting pits north of Butterdon Hill.
All the stone rows, the majority of the cairns and most of the settlement sites have been designated as Scheduled Ancient Monuments (SAMs).
The ecology of this consists of fragmented Western Heath, acidic grassland and bracken. No UK BAP species are known to be present in the area.
What it should look like: This site requires a mosaic of short acid grassland (less than 20 cm), heathland and extensive areas of Western Heath. An extensive programme of Bracken control should be carried out the eastern and southern edges and Bracken on enclosed land at Corringdon Ball will require management. It is important that management reveals the relationship between the ritual monuments on Ugborough Common.