Church of St Michael

The Church of St Michael is a Grade II* listed building constructed from coursed sandstone rubble, featuring very thick walls that show signs of rebuilding. The roof of the nave and chancel is covered with stone tiles, while the tower has a slate roof. The nave includes a large three-light south window with 15th-century tracery and a single small splayed opening in the north wall. The south doorway has a Tudor arch and is sheltered by an enclosed rubble porch with a half-timbered gable. The chancel is set back and has a gable drip course, with paired lancets on the east and south sides and a plain square-headed opening on the north.

The broad low tower is situated on a large mound and features a half-timbered bell stage that is smaller in section, topped with a pyramid roof. There is a small plain square-headed window in the north side of the tower.

The churchyard is circular and contains several low chest tombs with rubble bases and slab tops. The nave is a typical Radnorshire plain single cell and has a restored 15th-century roof with chamfered arch braces and cusped struts above the collars, along with three tiers of cusped windbraces. Inside, there is a 14th-century octagonal font on a square base and an inserted timber vestry partition at the west end. The chancel screen, originally from the 15th century, has been altered and lost its loft; it features a central square-headed opening with pierced quatrefoil tracery and five semi-circular arched openings with moulded uprights on a low dado. The chancel has a restored arch-braced roof from 1895, with a wall plate partially replaced in concrete. A wooden reredos from 1895 features elaborate oak paneling, and there is a triangular-headed aumbry. A memorial tablet commemorates William Jenkins Rees, Rector of Casob from 1806 to 1855, who was an editor of the Welsh Manuscript Society and an author prominent in the revival of the Welsh National Eisteddfod. The tower arch is lined with a primitive framework made of very large reused timbers, and the church houses two bells dated 1633.