This is the northernmost church of the Octagon Parish. Originally a chapel of ease to East Marden and perhaps always approached through a farmyard, St Mary's is believed to have been founded by Geoffrey, son of Azo, late in the 12th century. It consists of an undivided nave and chancel. The chancel has a semi-circular (apsidal) end, and is one of only six small churches in England that has one. The principal feature of the church is the elaborate Norman south doorway. Made of Caen stone, this was probably shipped across the channel to Chichester harbour and then transported by packhorse to North Marden. There is no electricity in the church.