The Basilica of Saint Sebastian Outside the Walls was part of the "Seven Churches" visited by pilgrims during the Jubilee. It built in the fourth century, on the site where, according to tradition, had been transferred to the relics of the Apostles Peter and Paul, to save them from persecution, and housed, in the underground catacombs, the body of the Roman martyr Sebastiano (later transferred to the Vatican). Constantine built the primitive Basilica following the circular model with three naves, preceded by a large rectangular atrium. In 1933 were the aisles were rebuilt, using the ambulatory which ran the fourth century. In the right aisle they are collected artifacts from the catacombs below, and placed the underground entrance to the cemetery; in the left aisle there is the Epigraphic Museum. The facade, by Giovanni Vasanzio, was finished in 1613, and consists of a portico with three arches at the bottom, which correspond to three large windows at the top. The interior has a single nave, with a carved wooden ceiling, representing the titular Saint and the coats of arms of Cardinal Scipione Borghese and Pope Gregory XVI. On the right side are: the Chapel of the Relics, decorated in 1625, in which are located a stone with the footprints of Christ and one of the arrows that killed St. Sebastian; on the left side you have the tombstone of Pope Damasus I, let carved by Furio Dionisio Philocalus; and the St. Sebastian's Chapel by Ciro Ferri (1672). The nave ends with the triumphal arch leading to the presbytery, a square with a dome. The main altar consists of a kiosk with four columns, it was designed by Flaminio Ponzio and is surmounted by the "Crucifixion" by Innocenzo Tacconi.