The west porch is like a church in itself beneath the cathedral, with some of the oldest and best-preserved original decoration. There are two chapels within the porch, dedicated to Saint Martin (south side) and Saint Luke (north). Their facades are from the original 11th-century church, before the construction of the two western traverses in the mid-12th century. The cedar doors, the carved and painted doors to the porch, were installed at the end of the 12th century. An inscription in Latin on the walls of the stairway warns in impure not to enter.