This feature, probably part of a fish trap, consists of a slightly curving arm measuring approximately 100m from end to end. One end points northwest with the other pointing southeast. Other fish traps in the Llanon complex consist dry stone walls, a single boulder high. It is probable that this fish trap is of similar construction.

Sources include:
National Assembly of Wales, 2005, vertical AP

Maritime Officer, RCAHMW, February 2011