But that unassuming circular bank is the outline of a rath, a type of enclosed farmstead that once formed the basic unit of rural life across early medieval Ireland. Thousands were built, typically between the sixth and tenth centuries, and yet each one that survives intact in the landscape is quietly remarkable for having outlasted so much else.

This particular example sits north of the Owenkeagh River in Ahalisky, in the west of County Cork. It measures roughly 38 metres in diameter, with an earthen bank still standing about 1.3 metres high. A rath of this kind would originally have enclosed a family's dwelling house, outbuildings, and animals, the bank providing a boundary that was as much social and legal as it was defensive. At Ahalisky, the interior is now overgrown, and a ring of conifers planted along the bank gives the whole thing an oddly deliberate, almost ornamental appearance from a distance, though that planting is almost certainly a practical modern addition rather than any ancient intention.