At the east end of the nave is the vaulted sanctuary apse and at the west end a great narthex or vestibule, beyond which an exonarthex opens to the forecourt, or atrium.

• 在中央广场东部末端的半圆形后殿的拱状避难所，在西部末端的教堂前厅或门廊，较远一点的就是直达前院的教堂前厅，或者中庭。