St. Mary's Church

St. Mary's Church is a Grade II* listed building with origins dating back to the late 13th century, featuring a nave, possibly a 14th-century porch, an original chancel, and a south transept, all constructed from local limestone masonry. The nave is notable for its steeply pointed vault, while corbels in the porch indicate it once had an upper floor, which has since been removed. There was also a north aisle that was demolished in 1770, with its arcade still visible from the outside. Evidence suggests the presence of a rood loft.

In 1855, significant restoration was carried out by Lord Cawdor, with architect David Brandon from London overseeing the work. This restoration included the addition of a new chancel and the renewal of windows throughout the church in a lancet style. The chancel features Minton tile paving adorned with the Arms of Lord Cawdor and those of Bishop Thirlwall of St David's, along with a wide chancel arch supported by Early English corbel caps.

A large tower, likely added in the 15th century, is constructed from large-coursed rubble masonry and has a battered base. It includes a stair turret at the northwest corner, with the ground storey vaulted to a height nearly equal to that of the nave's vault. The upper storeys feature octagonal vaults, with the lower vault supported by thick ribs with chamfered arises. The parapet is carried on corbels, and the original west doorway in the tower is now blocked.

Around 1870, an octagonal stone spire was built on the tower by the Admiralty as a navigation landmark, replacing an earlier timber spire. A memorial to Colonel Leach, created by Eric Gill in 1936, is also located within the church.

Further restoration was conducted under the Castlemartin Trust, established in 1986, to serve as an interdenominational church for British and German troops at Castlemartin Range. The altar, made in Bergen, Germany, incorporates a stone altar slab from Rhoscrowther, while the font is supported by a round pillar with a square base, and its cover was also crafted in Bergen. Mendelssohn's organ was repaired and installed in the nave in 1988.

St. Mary's Church is recognized for its restored medieval architecture, featuring a fine west tower and spire.