San Clemente al Laterano. The Basilica of Saint Clement is a Roman Catholic minor basilica dedicated to Pope Clement I located in Rome, Italy.
   Archaeologically speaking, the structure is a three-tiered complex of buildings: the present basilica built just before the year 1100 during the height of the Middle Ages; beneath the present basilica is a 4th-century basilica that had been converted out of the home of a Roman nobleman, part of which had in the 1st century briefly served as an early church, and the basement of which had in the 2nd century briefly served as a mithraeum; the home of the Roman nobleman had been built on the foundations of republican era villa and warehouse that had been destroyed in the Great Fire of 64 AD. This ancient church was transformed over the centuries from a private home that was the site of clandestine Christian worship in the 1st century to a grand public basilica by the 6th century, reflecting the emerging Catholic Church's growing legitimacy and power. The archaeological traces of the basilica's history were discovered in the 1860s by Joseph Mullooly, Prior of the house of Irish Dominicans at San Clemente.
   The lowest levels of the present basilica contain remnants of the foundation of a possibly republican era building that might have been destroyed in the Great Fire of 64. An industrial building-probably the imperial mint of Rome from the late 1st century A.D. onwards
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