Cass ny Hawin

Cass ny Hawin is the site of both a Mesolithic settlement and an Iron Age and Viking promontory fort.

The area of Mesolithic activity is located some 200m south of the promontory fort, just beyond the northern end of the modern promontory constructed in 2008-9 to accommodate the extended airport runway. Surface scatters of flint tools were first recorded during the 1900s and later erosion of the cliff-face in the 1980s led to the discovery of a hollow measuring 3.4m by 1.9m and filled with dark charcoal-stained soil that contained microliths and a hearth. There were no remains of a roof, but timber rafters covered with vegetation could have spanned the hollow. There were quantities of hazelnut shells, suggesting that the hollow was occupied during autumn, perhaps as a temporary structure for hunter-gatherers, or as a food processing area and later as a rubbish dump. The flint tools recovered included an unusual ‘tanged’ arrowhead, often associated with much later prehistoric sites, but the site was dated using radiocarbon dating to around 5700BC. Some of the artefacts from the site are on display in the Manx Museum. More finds were discovered in the course of the extension of the airport runway, which confirm that this area attracted significant human activity soon after the end of the Ice Age when the change in climate allowed the first explorers and settlers to colonise the Island.

The promontory fort has been eroded through the years and the defensive rampart which protects the headland on the landward side has been reduced to a less impressive size, as has the accompanying ditch. The rampart was once faced on both the inside and outside with stone walling which retained the earthen bank. This was built on the remains of an earlier rampart on a slightly different alignment. Outside the rampart are the remains of a shallow ditch, 10m wide and 1m deep, cut into the underlying rock. Any sign of an entrance or gateway has been lost to erosion. Several postholes and post trenches were found to the south-west which passed beneath the rampart. These may be the remains of a timber defence such as a palisade, or even a roundhouse, belonging to the original phase of occupation.

Today the interior of the promontory fort is empty, but excavations revealed evidence of a rectangular building, measuring 10m by 4.5m, and orientated east/west. The walls of this structure were almost 2.5m thick and were constructed entirely of turf. Before the structure was built, the ground was cleared to the underlying rock and this surface formed the floor. A shallow channel about 1.5m wide had been excavated into the underlying rock down the centre of the building, creating two raised areas, or ‘benches’, along the long walls of the structure. There was evidence of a makeshift inner doorway beyond which was a covered passageway leading to outer doorways in the north and south walls. Postholes in the interior suggested that the roof was of a hipped configuration. The interior had a rather basic central hearth and the remains of what may have been a small clay oven.

The features of this structure, particularly the ‘benches’, are typical of a Viking period building. A small number of pieces of pottery dating to the 13th century, including locally-produced granite-tempered ware, were recovered during the excavation. There were, however, very few domestic artefacts, though a broken set of iron shears from the site are on display in the Manx Museum.

This site overlooks a small natural inlet at the mouth of the Santon Burn, a potentially vulnerable point on the coastline requiring protection from raiding, or even invasion. Sites such as Cass ny Hawin, which have produced few overt signs of true domestic activity, may have formed part of the Island’s coastal defence system, Watch and Ward, which provided fortified lookouts and deterred prospective attackers. It may also be that this, and other bays and inlets associated with promontory forts, were used as beach markets, places where boats and even ships could land and trade goods during the Medieval period. It is probable that such beach markets were regulated, and that levies were collected by officials who may from time to time have required some form of accommodation.

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