The ancient Roman palace that became the world's oldest public church

Countries & Cities · Published 29 September 2026 Swipe more like this →

In short: Long before the Vatican became the papal seat, a Roman family's estate held the keys to imperial power. Today, this site remains the only archbasilica in existence, a monumental structure built atop the ruins of an imperial cavalry fort and an ancient aristocratic palace.

The Archbasilica of Saint John Lateran, located just four kilometres northwest of Vatican City, serves as the seat of the Bishop of Rome. Its origins are deeply intertwined with Roman nobility; the name 'Lateran' derives from the gens Laterani, an ancient family whose palace once occupied the site. Following the political shifts of the early Empire, the property passed to Emperor Constantine the Great. During the pontificate of Pope Miltiaries, the site was transformed into the 'Domus Dei' or House of God, with an official dedication in 324.

The basilica's history is a saga of destruction and resurrection. It has survived devastating fires in the 14th century, specifically in 1308 and 1362, as well as a massive earthquake in 897 that caused the structure to collapse from the altar to the doors. Significant architectural shifts occurred during the late 16th century under Pope Sixtus V, who commissioned Domenico Fontana to lead a reconstruction. Later, in 1735, the current neo-classical façade was finished under the direction of Pope Clement XII, following a competition involving over 23 architects.

Beyond its religious significance as the 'mother church' of the world, the site holds layers of imperial history. The nave stands directly above the remains of the Castra Nova, a fort established by Septimius Severus in AD 193 for the emperor's mounted bodyguards. Even the massive Lateran Obelisk, which weighs approximately 455 tons, was brought to the site after being moved from the Circus Maximus. This architectural palimpsest continues to serve as a sanctuary, having famously provided refuge for Jewish citizens and refugees during the Second World War.

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