The Basilica of San Clemente al Laterano, located in Rome, Italy, is a three-tiered complex of buildings that offers a fascinating journey through time, delving into the layers of Roman and Christian history. It is a minor basilica dedicated to Pope Clement I. The present basilica was constructed in the 12th century with a richly decorated interior reflecting the apse mosaic, which is one of the most significant examples of early medieval art. The exterior of the Basilica is relatively modest, with a simple brick facade adorned with a beautifully detailed mosaic above the entrance, portraying the Tree of Life. The basilica's interior, on the other hand, is a feast for the eyes. The main feature is the stunning 12th-century apse mosaic, depicting the Cross as the Tree of Life. The flooring is a beautiful example of Cosmatesque style, a form of artistry specific to Rome and the surrounding region. The actual structure, however, only represents the topmost layer of the site. Beneath the basilica, there is a 4th-century basilica that had been converted out of the home of a Roman nobleman, part of which had served as an early Christian worship site. This basilica was abandoned in the 11th century and forgotten until its rediscovery in the 19th century. But the journey continues even deeper to reveal the ancient Roman buildings from the 1st to the 4th century AD, including a Mithraic temple. Mithraism was a mystery religion practiced in the Roman Empire from the 1st to the 4th century AD. The Basilica of San Clemente al Laterano is an architectural palimpsest, with each layer offering a glimpse into a different period of history. It's a fascinating blend of the ancient and the medieval, a place where you can quite literally walk through time. The Basilica is not just a place of worship, but a living, breathing testament to Rome's rich and layered history.