Another major basilica of Rome is The Basilica of Saint John at Lateran. Like St. Paul's Outside the Walls, this building is one of the major basilica's of Rome and also has its own dedicated train stop (San Giovanni). Unlike St. Paul's, and indeed most Basilicas, St. John Lateran is distinguished by having a feast day on the liturgical calendar — not the Saint which the building is named after but the building itself.
Though renovated over time, the building was built in the fourth century and was originally a palace built by Constantine. An important seat of power, the structure transitioned from Roman to papal hands and eventually became Rome's Cathedral. Though some might assume that title belongs to Saint Peter's Basilica, the Cathedral of Rome is in fact Saint John Lateran — the Pope's Cathedral.
Lateran is also famous for being the sight of five of the twenty-some Ecumenical councils deciding important doctrinal clarifications in the Catholic Church such as lay investiture where civil rulers would try to install bishops. But by far the most peculiar of facts about Lateran is that it contains the heads of Saint's Peter and Paul. Though their bodies are buried under their own basilica's respectively, their heads were separated and sit above the altar encased in statuary. An important historical building with a beautiful interior, Saint John Lateran is well worth the visit.
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Pilgrimage: From the Ganges to Graceland: an Encyclopedia, Volume 1 By Linda Kay Davidson, David Martin Gitlitz