This crypt was discovered by chance in 1956, on a site where a parking lot was planned. Martial and his two companions were buried here in two large sarcophagi. In the opposite corner is the paved loggia where the tomb of St Valerie, possibly a Merovingian benefactor, was placed. After you have crossed the room containing an enormous granite sarcophagus (4C), you will come to the foundations of two churches, Église St Pierre and Église St Benoît, which stand on the site of an early-Christian cemetery.