The Museum of the Order of St John The Museum of the Order of St John tells a unique and fascinating story about the Order of St John — from its origins in eleventh century Jerusalem, through to its role today with St John Ambulance and the St John Eye Hospital in Jerusalem. The Museum occupies two sites in Clerkenwell, London: St John’s Gate, the entrance to the former Priory of the Knights of St John, which dates from 1504; and the Priory Church of St John, Clerkenwell with its surviving twelfth century Crypt. Visit the Museum website to find out more