Third Sunday of Lent
The first church at the present site of Basilica of St. Lawrence Outside the Walls was built by Constantine. Next to it was another church built by Pope Sixtus II. The two churches were so close to each other that eventually the walls that separated them were torn down to form a single basilica. Damaged by a bomb by the Allies in 1943, it was beautifully restored in 1948. Along with the 4 major basilicas, it is one of the five patriarchal basilicas in Rome. A patriarchal basilica was historically assigned to each of the 5 ancient patriarchal sees (Pentarchy):
Basilica of St. John Lateran: Patriarchate of Rome
Basilica of St. Peter: Patriarchate of Constantinople
Basilica of St. Paul: Patriarchate of Alexandria
Basilica of St. Mary Major: Patriarchate of Antioch
Basilica of St. Lawrence: Patriarchate of Jerusalem
There are two other patriarchal basilicas in Assisi that have great historical significance: the Basilica of St. Francis, and the Basilica of St. Mary of the Angels. Despite the name, neither of them has a patriarchate assigned to it. I'll talk about these basilicas some other time.
Since 2006, Pope Benedict XVI decided to stop using the title "patriarchal basilica" in these seven churches. Since then, they have instead been known as papal basilicas.
Under the main altar is the tomb of St. Lawrence, and the protomartyr St. Stephen (both deacons). The body of St. Stephen was transferred from Constantinople by Pope Pelagius II. Read about the story of the deacon St. Lawrence in the blog entry of the station church of Thursday of Week I of Lent. Pope Pius IX is also buried in this basilica.
As a papal basilica, it is not a titular church. While the four papal major basilicas have archpriests who act as delegates of the pope, the papal minor basilica of St. Lawrence is governed by a commendatory abbot. The parish is now served by Franciscan Capuchins. Avoid the hours of noon to 4 pm on weekdays to visit the basilica when it is closed.