Round Churches were imitations of the Holy Sepulchre at Jerusalem, the nave being round and forming the vestibule of an oblong chancel, as in the Templars' churches at Laon, Metz, and Segovia, 1208. Other examples are found in Ludlow Castle, Cambridge, Northampton, of the end of the 12th century; Little Maplestead (built by the Hospitallers), St. Gereon's, Cologne, of the 13th century; Treves, Bonn, Aix-la-Chapelle (a copy of St. Vitalis, Ravenna, and more remotely of St. Sophia, Constantinople), Salamanca, St. Benignus at Dijon, London, built in 1185; Neuvy St. Sepulchre, cir. 1170; Lanleff; Rieu Minervois, of the close of the 11th century; Brescia, Pisa, Rome, Bergamo, Bologna, Thorsager, and several other churches in Scandinavia. In many cases the shape may have been merely a mechanical contrivance to carry a dome. Circular churches occur of all dates, and distributed over most parts of Europe, either insulated as baptisteries, in a mystical allusion to the Holy Sepulchre, attached as chapels to churches, or existing as independent buildings. They are sometimes of a simple round or polygonal form, either without recesses, except an apse or porch, such as the church of Ophir, Orkney, and the baptistery of Canterbury, or with radiating recesses, rectangular or apsidal, as the baptisteries of Novara and Frejus. Sometimes a circular or polygonal center is supported by pillars, and surrounded by an aisle of corresponding form: this aisle is repeated at St. Stephen's, Rome, and Charroux. The Crusaders, or pilgrims, imitated the plan of the Sepulchre of Jerusalem, surrounded by a circular church, and the Martyrdom, or place of the crucifixion, by a chancel eastward of a round nave. At Bury St. Edmund's, at the close of the 11th century, the abbot removed the body of St. Edmund from the "round chapel" to the new church; and this circular termination is still seen in Becket's Crown at Canterbury, at Sens, Burgos, Batalha, Murcia, and Drontheim. After the middle of the 13th century round churches were no longer built. Almost all the German churches of the time of Charlemagne were circular, like Aix, Nimeguen, Petersburg, and Magdeburg.