The west entrance of the church leads into a dark narthex (late 10th or early 11th century) with a low, heavy vault. Like the nave, it has three aisles supported by plain round pillars. The center aisle is groin vaulted and the side aisles are barrel vaulted; some are decorated with frescoes. There are many tombstones embedded in the floor, including some interesting round ones from the 16th and 17th centuries that may cover funeral pits. The narthex is more substantial than most because it supports a large chapel above. The contrast as one leaves the dark narthex and enters the tall, bright nave is a spectacular effect.