These flat-topped, steep-sided structures have puzzled archaeologists and locals alike, their origins and purpose lost to time. The first mound stands 1.33 metres tall with an oval base measuring 11.5 metres southwest to northeast and 16.2 metres northwest to southeast, tapering to a top platform of 8 by 11.7 metres. Its companion, located slightly to the southeast, rises even higher at 1.71 metres, with base dimensions of 16.1 by 18.1 metres narrowing to a summit of 9.4 by 11.6 metres.

Both mounds are primarily constructed from compacted earth, though stones protrude through their tops, hinting at possible internal structures or later disturbance. The second, taller mound features a particularly intriguing element: a substantial stone slab measuring 3.6 metres long and varying between 0.55 to 1.17 metres wide, positioned on its eastern side. This slab might represent a collapsed chamber entrance, a deliberate marker, or perhaps evidence of past excavation attempts.

While their exact age and function remain uncertain, these mounds likely date from prehistory, possibly serving as burial monuments, ceremonial platforms, or territorial markers. Their prominent position overlooking the estuary would have made them visible landmarks for anyone travelling along this ancient coastline. Today, they stand as enigmatic reminders of Donegal's deep past, their weathered forms continuing to command the landscape much as they have for centuries, if not millennia.