The Chapel of St Peter-on-the-Wall, Bradwell-on-Sea, Essex is probably the oldest Christian churches in England in regular use. It was built in 654 AD by St Cedd astride the foundations of the abandoned Roman fort of Othona. From the 14th century it was used as a barn and consequently it likely retains its original Saxon form. In 1920 it was restored as a chapel. It is a Grade I listed building.