Overton is perhaps best known for the magnificent ancient yew trees in the churchyard, one of the Seven Wonders of Wales. The oldest is thought to be 1500-2000 years old. The church tower dates from the 14th-Century and houses a peel of 6 bells, and a clock by Joyce of Whitchurch incorporating their patent escapement mechanism, in common with Big Ben. The Norman circle cross, built into the west pillar of the nave, is probably the oldest stonework, and the weathered shaft of a 14th-century cross stands beneath a yew tree. An oak chest with heavy iron work probably dates from the 15th-century. Much older still, believed to date from the 6th-century, is an unusual Abyssinian brass processional cross with a calendar stick in Indian script. Other treasures to seek out are an east window by Clayton & Bell, 3 Kemp windows in the south aisle (1890), with Kemps Wheatsheaf signature on the clasp of the Magis cloak.