A crypt is a stone-built underground chamber or vault located beneath the floor of a church, cathedral, or other religious building, traditionally used for burials, the veneration of relics, or as a secondary chapel. Crypts have been a feature of Christian architecture since the early centuries of the faith.
Applications
Crypts originated in the early Christian period, when believers gathered at the tombs of martyrs and saints for worship. As churches were built over these sacred burial sites, the underground spaces were preserved and formalized into architectural elements. The crypt allowed pilgrims to access relics and tombs without disrupting services in the main church above.
In Romanesque and early medieval architecture, crypts became elaborate structures in their own right. They typically feature low vaulted ceilings supported by sturdy columns or piers, creating atmospheric, dimly lit spaces. The crypt of Canterbury Cathedral and the crypt of the Basilica of San Miniato al Monte in Florence are well-known examples of this architectural tradition.
Structurally, crypts are built using robust masonry techniques to support the weight of the church above. Barrel vaults, groin vaults, and later ribbed vaults were commonly employed. Because crypts are partially or fully below ground level, they also required careful attention to waterproofing and drainage, challenges that builders addressed with sloped floors, drainage channels, and thick stone walls.
Over time, the function of crypts expanded. In addition to housing relics and burials, they served as treasuries for church valuables, meeting spaces, and secondary worship areas. Some crypts are large enough to function as full churches in their own right, with altars, naves, and aisles.
In modern construction, the term crypt is sometimes used more broadly to describe any underground burial vault, including those in secular cemeteries and mausoleums.
Related terms
- Vault (architecture)
- Undercroft
- Catacomb
- Nave
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