It is just large enough to have been defended, and at some point in the past, someone made the effort to do exactly that. This is a promontory fort, a type of coastal enclosure in which a headland is cut off from the mainland by one or more earthwork barriers, effectively using the sea on three sides as a natural wall. What makes this particular example quietly striking is how slight its remains are, and how resolutely it keeps its secrets. There is no trace of an entrance. The flat interior holds nothing but rocks thrown up from the sea. It sits in a landscape of flat sheep grazing, overlooked by higher ground inland, and it was not formally recorded until relatively recently.

The fort is separated from the mainland by a fosse, a ditch dug across the neck of the headland, measuring three metres wide. Erosion along the southern cliff face has since exposed a section through the defences, revealing that the fosse may originally have been up to one and a half metres deep and was possibly partly rock-cut, suggesting more substantial effort than the present surface impression implies. Regular stone uprights found four metres outside the fosse may be the remnants of a wall that once ran across the headland's neck, and there are faint indications of a further stone wall just beyond the fosse itself. The site was previously unrecorded, and the descriptions of it derive from a 1999 MA thesis by Markus Casey, a survey of coastal promontory forts across Sligo, Mayo, Galway, and Clare. The fort sits immediately south of another fortified headland, and to the southwest lie a further promontory fort and several hut sites, suggesting this stretch of the Mullet's Atlantic edge was once a good deal busier than its present emptiness suggests.