The tour in St. Clement’s basilica starts from the wonderful church built at the end of the XI century by will of cardinal Anastasius, where we can admire the beautiful mosaic in the apse representing the Cross as arbor vitae, the marble schola cantorum and the chapel dedicated to St. Catherine, decorated with frescoes by Masolino da Panicale (1428-1431). Going down under the basilica, we can see the remains of the previous church from the IV century AD, with wide portions of Early Medieval frescoes telling stories of St. Alexius and St. Clement, and among them the very famous scene with one of the earliest attestations of Italian language. Going further down, we reach the level of two large buildings, dating from the period immediately after the big fire in 64 AD under emperor Nero. One of those buildings, starting from the middle of the III century AD, hosted a sanctuary dedicated to the god Mithra, destroyed when the Christian church was built.
