These cloisters were built from new and decorated in the Cosmatesque style in the 13th century. The cloisters form a perfect square, 36 meters on each side and with four interconnected ambulatories or covered walkways

There are many items of ancient and medieval sculptural work displayed here, which have been discarded from the basilica in renovations from the 16th century to the 19th. So, the outer walls of the ambulatories of the cloisters are serving as the sculpture gallery of the basilica's museum.