The church of All Saints in Oystermouth was first mentioned in documents in 1141, when Maurice de Londres received income from it. It was probably built on the ruins of a Roman building. In the 19th century, due to the increasing population of the rapidly developing city and the poor technical condition of the temple, the church was renovated and expanded with a new northern nave. In 1915, the Victorian annex was dismantled to make room for the larger nave and chancel. These works were completed until 1937, and as a result, the medieval church became the southern nave and chapel (former presbytery) of the new temple.
The medieval church consisted of a nave on the plan of a rectangle, eastern chancel, porch and tower on the western side. The tower is crowned with a parapet on corbels and crenellation, from the south side has a projection in the wall housing a staircase. The original entrance to the church was on the south side of the nave, today it is walled up. A narrow ogival window from the 13th or 14th century has been preserved next to it, and a three-light window in a rectangular frame from the 16th century. The presbytery in the eastern wall has three lancet, narrow windows, originally from the 14th century, but renovated in the 19th century.
Website britishlistedbuildings.co.uk, Church of All Saints, Oystermouth A Grade II Listed Building in Mumbles (Y Mwmbwls), Swansea.