Today, this enigmatic site appears as little more than a grassed-over outcrop of rock, roughly circular in shape and measuring about 20 metres north to south and 23 metres east to west. The platform commands its position with steep drops on the northern and eastern sides, whilst gentler slopes descend to the south and west, surrounded by the rolling pastures that characterise this part of the Donegal landscape.

The fort at Greenhill represents one of countless archaeological sites scattered across County Donegal, each telling a fragment of the region’s complex history. Though no visible traces of defensive structures or occupation remain, the site’s strategic positioning on elevated ground suggests it once served as an enclosure, possibly dating from the early medieval period when such fortified sites were common throughout Ireland. The natural defences provided by the rocky platform would have been ideal for a small settlement or defensive position, offering clear views across the surrounding countryside.

This description comes from the comprehensive Archaeological Survey of County Donegal, compiled in 1983 by Brian Lacey and his team of archaeologists. The survey documented field antiquities spanning from the Mesolithic period through to the 17th century, creating an invaluable record of sites that might otherwise be forgotten. Though the Greenhill fort has left no dramatic ruins or impressive earthworks, its inclusion in both the historical maps and the archaeological record ensures its place in the narrative of Donegal’s ancient landscape.