Cleigh yn Arragh

Cleigh yn Arragh is a large earthen bank and ditch crossing the ridge between the Lhergyrhenny and Tholt y Will valleys. It is a very obvious feature in the landscape, its sheer size leading to suggestions that it is an Iron Age defensive structure, similar to those at South Barrule. Another speculation is that the King and later the Lord of Man had a deer-park in the area and that the bank and ditch formed part of its boundary.

The bank rises to a maximum of over 2 metres in height near the top of the ridge and the excavation of earth used to construct it has left a large ditch 3-4m wide on the uphill side. To the north of the road the bank reduces in size before curving westwards and petering out close to the Tholt y Will stream. Surface water flowing along the quarry ditch has transformed it into a gulley. Today it is difficult to see any obvious way through the bank and ditch, other than where the modern roadway is located.

It is hard to see Cleigh yn Arragh serving a defensive role, as the ditch ought to be on the downslope side of the bank to have most effect. Instead, it seems more practical as an obstacle to prevent livestock upslope from moving downhill.When considered from this perspective it is tempting to see it as an unusually massive example of the ‘mountain hedge’ which historically separated common land from farm land and prevented animals pastured on the uplands during the summer from trampling crops as harvest time approached. The location and form of the mountain hedge varied through time as common land was from time to time enclosed under licence and the massive earthen banks formerly employed were replaced with cheaper stone walls. It is noteworthy that the bank and ditch have been cut by the boundaries limiting the farm of Lhergyrhenny, a landholding created by one such licensed enclosure, and that subsequent agricultural activity has reduced the earthwork and filled the ditch which formerly extended all the way to the valley bottom to the south.

It is possible that Cleigh yn Arragh was associated with the office of the king’s forester, an official based in Sulby glen who was responsible for regulating activities on the unenclosed uplands, dealing with stray stock and levying payments on its users. Without finding some datable deposits or artefacts through archaeological excavation, however, the origin of the bank and ditch will remain uncertain.

Text from 'A Guide to the Archaeological Sites of the Isle of Man' by Andrew Johnson and Allison Fox.