It is easy to walk past without registering what it is, the posts looking at first glance like the remnants of something incidental, a broken jetty perhaps, rather than evidence of an organised and once-productive fishing system.

A fish weir of this type works on a simple principle: stakes are driven into the mud or sand in converging lines, often with wicker or netting between them, so that fish carried in by the tide become trapped as the water falls back. The structure here, documented by Aidan O'Sullivan in 2001, consists of a double row of posts running roughly north to south along the upper foreshore on the north bank of a creek, measuring approximately twenty metres in length. O'Sullivan dates it to the post-medieval period, a broad classification that generally covers the sixteenth century onwards, suggesting it was part of the working life of this stretch of the estuary well into historical times. The Shannon's intertidal zone preserves organic materials with unusual reliability, and post alignments like this one, which might otherwise have decayed entirely on dry land, survive here in the waterlogged sediment.