Anglo-Saxon turriform churches were an Anglo-Saxon style of church that were built in the form of towers. They can also be called tower-nave churches. Several Anglo-Saxon churches were built as towers. The ground floor was used as the nave; there was a small projecting chancel on the east side and sometimes also the west, as at St Peter's Church, Barton-upon-Humber (the baptistery). Archaeological investigations at St. Peter's in 1898 revealed the foundations of the original small chancel; marks on the east wall of the tower also show where its walls were, and that it was narrower than the tower. Later, in this case in the fourteenth century, the chancel was replaced with a nave extending eastward from the tower.