At the centre of the nave are the foundations of an ambone, a raised pulpit reached by twin stairways. From here, priests would read passages from the scriptures to the congregation, making it one of the focal points of the church's ceremonies. The nave itself was reserved for the clergy. During services, priests would have processed around this space while the congregation gathered in the side aisles. These aisles were separated from the central nave and were usually paved much more simply, with rough stone slabs, tiles, or even packed clay.