The building which now houses the Wignacourt Museum was built in 1749 to house this collegiate. It is constructed in the Baroque style, and it contains three levels. The underground level is linked to St. Paul's Grotto, and it also contains a number of Punic, Roman and Early Christian hypogea which are interconnected with a complex of World War II-era air raid shelters. The building includes a garden and a small chapel, which was originally used for private worship by the chaplains.
