That uncertainty is not a caveat to be quickly passed over; it is the most interesting thing about the site. As of 2003, the earthworks here had been observed only from the air, and no one had confirmed them at ground level, leaving the place in an unusual state of archaeological suspense.

What the aerial observation recorded was suggestive: a double wall or bank and fosse, cutting off an area of ground to the south of a natural swallow hole, a point where the land simply opens and drops into darkness. A fosse is a defensive ditch, and when paired with a bank or wall it forms the characteristic barrier of a promontory fort, a type of enclosure that uses a narrow neck of elevated coastal land as natural defence on several sides, requiring only a constructed barrier across the landward approach. A second headland immediately to the north showed a depression running across its narrow isthmus, hinting that this too may have been enclosed at some point. The landscape around both features is described as mountainous bog with outcropping rock, difficult terrain that offers its own explanation for why ground verification proved elusive. Higher ground to the east overlooks the whole area, adding to the sense that this is not an easy place to move through or to read.

Promontory forts are found all along the Irish Atlantic coast and are generally associated with the Iron Age, though dating individual examples is notoriously difficult without excavation. Whether the earthworks at Laharan represent genuine prehistoric activity or are the result of natural geological processes acting on boggy, rocky ground remains an open question. The swallow hole alone, a feature formed when surface water erodes soluble rock beneath and the ground above collapses, gives the landscape an unsettled quality that makes the ambiguity feel fitting.