What makes this one quietly peculiar is its situation: Annaghroe Island sits so close to the shore that a causeway connects the two, marked simply as "Ford" on the 1930 Ordnance Survey six-inch map, suggesting the crossing was always as matter-of-fact as the island itself.

The rath occupies the eastern side of the island and measures roughly 27.6 metres north to south and 31.9 metres east to west, giving it a subcircular shape that is broadly typical of the form. What time has left is a slumped and partly levelled scarp, still standing about 1.5 metres high at the south-east but reducing to around 0.7 metres at the north, with a slope four to five metres wide. A faint raised rim survives along parts of the southern and western interior edge, a ghost of the original bank. The 1838 and 1930 Ordnance Survey maps both show field boundaries running up to the rath on its western and northern sides, but those boundaries have since been removed, leaving the structure without even those incidental neighbours to give it a sense of scale or agricultural context.

The causeway that provides access to the island is a recorded feature in its own right. Visitors approaching from the shore should expect a crossing that was clearly in use for generations, though the ground around both the causeway and the rath itself will reflect the soft, often waterlogged character of a lake island in the west of Ireland.