Basilica of San Nicola in Carcere

This medieval church was built directly into the ruins of three ancient temples that once stood in a Roman market district near the Tiber, and their columns are still embedded in its outer walls. The nave incorporates mismatched antique columns of varied marble, and an underground level lets visitors walk among the temple foundations beneath the church. A slender Romanesque bell tower rises alongside. The fusion of pagan temples and Christian church makes it a vivid example of Rome's reuse of its past.