Inside the Basilica: Millennial mosaics : Mosaic cycles of the fifth century which are among the most valuable in the world for state of preservation and historical importance. Layered architecture: The interior has an early Christian structure, the exterior has a Baroque facade and the tallest Romanesque bell tower in Rome. Religious treasures: It houses the relic of the Holy Cradle (the Bethlehem nativity scene) and the famous Salus Populi Romani icon. The "Miracle of the Snow": Legend has it that it was built where it snowed inexplicably on August 5, an event recalled every year with a rain of white petals. Inside the Museum Areas there is a visit whose entrance ticket includes free admission to the Loggia delle Blessings, Hall of the Popes, Bernini's Staircase and the Liberian Museum.