San Nicola in Carcere

A medieval church in the ancient Forum Holitorium (vegetable market) that incorporates three complete Republican-era temples within its walls — their ancient columns are visible embedded in the church's flanks and inside the interior. Built in the 11th century on the ruins of three temples dedicated to Janus, Juno Sospita, and Spes, it is one of the clearest examples in Rome of the city's habit of literally absorbing ancient structures into Christian buildings. The underground excavations (accessed from inside the church) bring you face to face with the original ancient foundations, temple podia, and the extraordinary layer-cake of Roman history. Near the Theatre of Marcellus and the Jewish Ghetto. One of Rome's great "hidden in plain sight" ancient-Christian fusion sites.