St Philip's Church, also known as Caerdeon Chapel, is situated off a steep lane, in a dramatically sloping churchyard. The churchyard is bordered by a stream on its southwest, and approached via the lych gate (NPRN 43900) within its eastern boundary. The church was built in 1862, in order to provide a place for English language worship, particularly the Oxford undergraduates who came to Caerdeon Hall (NPRN 308044) for Classics tuition. it was licenced as a private chapel for the use of owner of the Caerdeon estate, W E Jelf, and friends. Jelf was taken to the Court of Arches by the local incumbent, the Rector of Llanaber, who refused to conduct services in English. As a direct result, the Bishop of Bangor introduced a Bill into the House of Lords, legalising English services in Welsh speaking areas. This lead to the English Services in Wales Act 1863. The church was not consecrated until 1875.

The church is a Grade II* listed building and was designed by Jelf's brother-in-law, Rev John Lewis Petit (the only known building designed by him), a noted writer on continental architecture. The asymmetrical cruciform building is said to reflect the general rusticity of upland Mediterranean areas, but also uses local building materials and traditions to blend into its North Wales landscape. The original building consisted of the present aisleless nave, and was a rectangular building with plain rectangular windows. It had a rough loggia over the entrance, supported on square pillars. The chancel, with south transept and vestry, together with the bellcote, are sensitive later additions. The impressive bellcote is located over the crossing. It is divided into four, and is of particular interest owing to a mechanism which enables all the bells to be rung from a wheel-operated single rope. All roofs except that of the nave have been re-slated. An inscribed tablet, dated 1896, in memory of Jelf and Petit and his wife is located within the entrance logia. When private patronage ceased the church became subject to the Governing Body of the Church of Wales.

Sources include:
www.churchinwales.org.uk/parishholding/bangor/b508-en/history-en/st-philips

N Vousden, RCAHMW, May 2012