With soaring temperatures this summer there is no place cooler to hide than in the secret world beneath the streets of Rome. Explore the catacombs and crypts of the city’s most significant monuments, and unearth some of Rome’s best-kept treasures.

Often overlooked by the nearby Colosseum, the Basilica of San Clemente is a hidden gem that is definitely worth a visit. This three-tiered complex consists of an 11^th century Basilica that was built on top of the pre-existing 4^th century ”domus ecclesiae” (a secretive meeting room for early Christian worshippers) of martyr San Clemente. Go deeper under the Church and you’ll find a vault from the 3^rd century AD.