crypt

A crypt (from Greek κρύπτη (krypte) crypta "vault") is a stone chamber beneath the floor of a church or other building. It typically contains coffins, sarcophagi, or religious relics.
Originally, crypts were typically found below the main apse of a church, such as at the Abbey of Saint-Germain en Auxerre, but were later located beneath chancel, naves and transepts as well. Occasionally churches were raised high to accommodate a crypt at the ground level, such as St Michael's Church in Hildesheim, Germany.

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