The basilica was begun by Emperor Maxentius who reigned from AD 286 to AD 305, and completed by Emperor Constantine. The plan was a large nave, with three aisles on each side, of which only the northern part, that in the drawing, is still standing. The church was supported by eight fluted columns but only the one transported in 1613 to Santa Maria Maggiore is today extant. The draughtman reintegrated the column to the left part of the building and reduced the wall on the eastern side of the church so opening out the perspective.