Marked on the first and second editions of the Ordnance Survey 6-inch maps as both a ‘Fort’ and a ‘Cave’, this ancient structure has left no physical trace behind. The site, which sits in what was already good agricultural land, has been further improved for farming over the years, effectively erasing any remaining evidence of the fort’s existence.

The ringfort would have been a typical defensive homestead of early medieval Ireland, consisting of a single circular earthen bank and ditch that enclosed a dwelling area. These structures were common throughout the Irish countryside between roughly 500 and 1200 AD, serving as fortified farmsteads for prosperous families. The mention of a cave alongside the fort in historical records suggests there may have been natural features incorporated into the site’s defensive layout, or perhaps underground storage chambers known as souterrains, which were frequently built within or near ringforts.

Documentation of this lost monument comes from G.H. Kinahan’s 1886 survey work, later incorporated into the comprehensive Archaeological Survey of County Donegal compiled by Brian Lacey and colleagues in 1983. Whilst the physical fort has disappeared, its memory persists through these archaeological records, serving as a reminder of the countless historic sites that have been lost to agricultural improvement and development across Ireland. The transformation of the landscape at Drumhill reflects a pattern seen throughout the country, where productive farmland has gradually absorbed the earthworks and monuments of earlier inhabitants.