Vermin trap and length of reave 980m ESE of Trowlesworthy Warren House

Reasons for Designation

Dartmoor is the largest expanse of open moorland in southern Britain and, because of exceptional conditions of preservation, it is also one of the most complete examples of upland relict landscape in the whole country. The great wealth and diversity of archaeological remains provide direct evidence for human exploitation of the Moor from the early prehistoric period onwards. The well-preserved and often visible relationship between settlement sites, major land boundaries, trackways, ceremonial and funerary monuments as well as later industrial remains, gives significant insights into successive changes in the pattern of land-use through time. Warrens are areas of land set aside for the breeding and management of rabbits or hares. They usually include a series of purpose-built breeding places, known as pillow mounds and buries, vermin traps and enclosures designed to contain and protect the animals, and living quarters for the warrener who kept charge of the warren. Pillow mounds are low oblong-shaped mounds of soil and/or stones in which the animals lived. They are usually between 15m and 40m long and between 5m and 10m wide. Most have a ditch around at least three sides to facilitate drainage. Inside are a series of narrow interconnecting trenches. These were excavated and covered with stone or turf before the mound was constructed. Vermin traps of various kinds are found within most warrens. These include a small stone-lined passage into which the predator was funnelled by a series of ditches or walls. Over 100 vermin traps have been recorded on the Moor, with the majority lying in the Plym Valley. Warren boundaries were often defined by a combination of natural features such as rivers. Within the warrens themselves smaller enclosed areas defined by a ditch and bank are sometimes found, and some of these may have been specialised breeding areas. Many of the warrens on the Moor contain a house in which the warrener lived. Most of the surviving warren earthworks probably date to between the 17th century and the later 19th century, with some continuing in use into the early 20th century. At least 22 warrens are known to exist on the Moor and together they contribute to our understanding of the medieval and post-medieval exploitation of the area. All well-preserved warrens are considered worthy of protection.

The vermin trap may have been sited to take advantage of the already existing length of reave. Reaves are part of an extensive system of prehistoric land division introduced during the Bronze Age (about 2000-700 BC). They consist of simple linear stone banks, some of which are tens of kilometres in extent, used to mark out discrete territories. Both the vermin trap and reave 980m ESE of Trowlesworthy Warren House survive comparatively well and whilst both contain separate information relating to their very different functions, together they provide evidence for reuse of earlier prehistoric walls by warreners.

Details

This monument includes a vermin trap and a short length of reave situated near the summit of Little Trowlesworthy Tor overlooking the valley of the Blacka Brook. The vermin trap includes two lengths of drystone wall forming a `V'- shaped trap pointing towards a rock face. The position of the trap suggests that the rock face was intended to help encourage the vermin into the trapping area, which was originally sited at the point where the two lengths of walling meet. The northern wall measures 4.8m long, 0.5m wide, 0.5m high and is composed of orthostats. The southern wall is of rubble construction and measures 4.7m long, 0.8m wide and 0.3m high. Vermin approaching their quarry tend to seek a route that provides visual cover and the purpose of a trap was to funnel predators along ditches or beside walls to a central point where they could be trapped. This vermin trap forms part of Trowlesworthy Warren, which includes around 64 pillow mounds and 40 vermin traps scattered along the slopes of Little and Great Trowlesworthy Tors. The boundaries of the warren are denoted by the River Plym, Spanish Lake and Blacka Brook. Trowlesworthy Warren is generally accepted as the oldest surviving warren on Dartmoor, although recently doubt has been expressed concerning its medieval origins. However, it is known that the warren existed by 1651 when it was occupied by John Hamblin, a skinner from Plymouth. The warren appears to have remained in constant use from this time until the first half of the 20th century. The reave survives as a 3m wide and 0.5m high rubble bank leading southwards for 35m from Little Trowlesworthy Tor towards Great Trowlesworthy Tor. This reave may represent a continuation of another length of reave which lies to the north of the tor. Other archaeological features surviving within the vicinity of this monument are the subjects of separate schedulings. This monument is in the care of the Secretary of State.

MAP EXTRACT The site of the monument is shown on the attached map extract. It includes a 2 metre boundary around the archaeological features, considered to be essential for the monument's support and preservation.

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

22357

Legacy System:

RSM

Sources

Books and journals
Crossing, W, Crossing's Guide To Dartmoor, (1990), 431

Other
Robertson, J G, The Archaeology of the Upper Plym, 1991, Unpub. Ph.D. Thesis (Edinburgh)
Thackray, C., The Upper Plym Valley: The management of an historic landscape, 1994, Archaeological Site Inventory
Thackray, C., The Upper Plym Valley: The management of an historic landscape, 1994, Archaeological Site Inventory
MPP fieldwork by S. Gerrard, (1995)
Devon County Sites and Monuments Register, SX56SE215, (1972)

End of official list entry

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