This rough wall of boulders and large rocks stretches approximately 49 metres east to west across the channel, with an additional 11-metre section extending southeast from a natural rock outcrop. Built from dry-laid stones and now largely concealed beneath seaweed, the structure stands about three-quarters of a metre high and varies between two and three metres in width, effectively blocking the north-south flowing channel at low tide.

The causeway’s origins and purpose remain delightfully ambiguous, offering several intriguing possibilities. Historical maps from 1836 show a causeway-like feature here, whilst the 1907 Ordnance Survey indicates individual stepping stones, suggesting the current structure may have evolved over time. Its location is particularly significant; it provides a convenient shortcut to the medieval church of Templecrone and its associated sacred sites, including holy wells, a graveyard, and penitential stations that form part of a traditional turas, or pilgrimage route. This spiritual connection suggests the causeway may have served pilgrims making their way to these ecclesiastical monuments for centuries.

Yet there’s another layer to this maritime mystery. The causeway’s damming effect, which keeps the adjacent bay filled with water during most of the ebbing tide, hints at a more practical purpose. A small opening in the middle of the wall could have housed nets or baskets for catching fish, making this potentially a dual-purpose structure; both a pilgrim’s path and a fishweir. Some have even suggested it might have served as a dam for a tidal mill, though no physical evidence of such a structure has been found. Whatever its original purpose, this humble collection of stones represents a fascinating intersection of spiritual devotion and practical coastal engineering, quietly weathering the tides whilst keeping its secrets.