Gnejan Bay Pillbox is located on top of a cliff on the East side of Gnejna Bay. It is above and behind Beach Defence Post J3. A single loophole survives on each of the side walls, but the front wall facing the sea has fallen away. One of the loopholes is cut from solid stone.
This would appear to have been built as an emergency pillbox before the adjacent Defence Post was built.
It is close to collapsing into the sea and is in a poor state of repair.