Caldey Lighthouse

Caldey Lighthouse is a navigational beacon on Caldey Island in Pembrokeshire with a circular limestone structure reaching about 17 meters tall and walls nearly one meter thick at the base. Its light beam extends about 13 nautical miles across the water, flashing three times every twenty seconds to guide vessels in Carmarthen Bay.

Trinity House commissioned Joseph Nelson in 1829 to build this maritime beacon to guide vessels in Carmarthen Bay. The tower was designed specifically for this purpose and has shaped the shipping history of these waters since then.

The lighthouse stands near a Cistercian monastery where monks have maintained a religious community on the island for generations. The two structures together shape the spiritual character of this remote location.

The tower sits on an island, so access depends on ferry transport that varies with weather and tides. Plan to spend several hours for an island visit and bring flexibility with your timing.

This was the last Trinity House lighthouse to operate on acetylene gas before switching to electric light in 1997. The conversion marked the end of an era for this type of maritime beacon.

Location: Pembrokeshire

GPS coordinates: 51.63156,-4.68426

Latest update: December 14, 2025 11:03