The Siena Crypt was never actually used for the purpose of a crypt. It was never ever used as a place for burial but as a frescoed room that had the stairs leading to the nave of the Siena Cathedral. The tragic fact is that the crypt got damaged even before it became popular and thus was later used as a store room to keep building materials and other such items. The room was later cleaned and remodeled into what you can see now.