CATACOMBS
Catacombs
Catacombs are human-made subterranean passageways for religious practice. Any chamber used as a burial place is a catacomb, although the word is most commonly associated with the Roman Empire. Many are under cities and have been popularized by stories of their use as war refuges, smugglers' hideouts, or meeting places for cults.The above text is a snippet from Wikipedia: Catacombs
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