Continuing along the Via di San Giovanni in Laterano, immediately after San Clemente on the right we see the profile of the grandiose apse of the Church of the Santi Quattro Coronati, resembling more a medieval bastion than a church. Nor is this impression altered when we pass under the stocky bell tower or looking at the solitary square in front of the church from across the sharp arch which we passed. The old church was sacked and burned by the Normans and reconstructed by Pope Pasquale II, but in the new, much smaller construction the apse of the old, much larger church was incorporated. This explains the peculiarity of the apse, which is the sole example in Rome of where the apse touches all three naves. The church's name derives from the four Roman soldiers who refused to adore the statue of Esculapio and who were martyrred and then canonized. Its dark wooden ceiling dates from the 1500s and was offered by the Cardinal Enrico of Portugal. Also in the church is a gallery, 14th century frescos and pavement. The dark walls of the convent hide a picturesque, romantic and flower filled cloister dating from the beginning of the 13th century as well as the chapel of San Silvestro and its superb 13th century Byzantine inspired frescos. Let us now head towards the Romanesque portico of the Hospital of San Giovanni which we can see at the end of the modest Via dei Santi Quattro Coronati, and continue on towards the Piazza di San Giovanni in Laterano. The vast piazza is dominated by the colossal obelisk erected by Sixtus V where the statue of Marcus Aurelius once stood (later moved to the Campidoglio) It is the largest of the Egyptian obelisks in Rome, measuring without its base 32 meters tall. Put up in Thebes by the pharaohs 15 centuries before Christ, it was brought to Rome by Costanzo II, son of Constantine, in the year 357, for which a special ship with 300 rowers was built. It was placed in the centre of Circus Maximus, where it was found in three pieces in 1587. The back of the piazza is occupied by the Palazzo del Laterano, the side of the Church of San Giovanni, the Baptistry and the remains of a Roman construction. In this composition of mixed eras, the 20th century couldn't be lacking, and just behind the Baptistry is the Seminario Pontificio Romano, where young aspiring priests complete their study in a setting of sober elegance and modernity.