Baths of Diocletian

Interesting facts

In 1702 the astronomer Francesco Bianchini laid a meridian line in the floor of Santa Maria degli Angeli to check the calendar and fix the date of Easter.

The baths' octagonal hall served as the planetarium of Rome from 1928 until 1983.

The American sculptor Moses Jacob Ezekiel had his studio in the ruins from 1879 to 1910, receiving visitors such as Franz Liszt and Ulysses Grant.

The full dedication inscription survives only because a pilgrim of the 8th or 9th century copied it; the copy is kept at Einsiedeln Abbey in Switzerland.

Brick stamps show that the project absorbed Rome's brick industry, whose output was redirected under imperial control.

The church was dedicated to Christian martyrs who, according to tradition, died while the baths were being built.

From 1575 several surviving halls were turned into grain and oil stores for the city of Rome.

In the Middle Ages the ruins were known as the Palatium Diocletiani, the Palace of Diocletian, in the guidebook Mirabilia Urbis Romae.

The baths stand on the Viminal, the smallest of Rome's seven hills, and were fed mainly by the Aqua Marcia aqueduct.

The Smithsonian's National Museum of Natural History in Washington borrowed design elements from the baths, including their semicircular Diocletian windows.

Why it is worth it

The Baths of Diocletian were the largest bathing complex ancient Rome ever built, and a surprising amount of them is still standing, hidden in plain sight across the square from Termini station. Commissioned by Maximian in honour of his co-emperor Diocletian and built between AD 298 and 306, they covered an enclosure of about 13 hectares, with a central bathing block roughly 280 by 160 metres. An ancient writer claimed they could hold 3,000 bathers at once. The baths worked for more than two centuries, until the Ostrogothic king Vitiges cut Rome's aqueducts during the siege of 537, and the great halls then stood empty for a thousand years.

What makes the place extraordinary is how later Rome moved into the ruin rather than clearing it. In the 1560s Pope Pius IV had Michelangelo, then in his mid-eighties, convert the vaulted frigidarium and tepidarium into the basilica of Santa Maria degli Angeli e dei Martiri. Walking in from Piazza della Repubblica, you pass through a modest brick facade and find yourself under Roman cross vaults resting on colossal ancient columns, a volume that still conveys the scale of an imperial bath hall better than any reconstruction drawing. The piazza itself follows the curve of the baths' great exedra, and the round church of San Bernardo alle Terme, built in 1598, occupies one of the circular halls that once marked the corners of the enclosure.

The rest of the complex is the original seat of the Museo Nazionale Romano, founded in 1889. Here the Carthusian monastery that grew up inside the ruins has its great cloister, begun in 1565 to a design attributed to Michelangelo and a hundred metres on each side, an unusually vast and quiet space lined with ancient statues, sarcophagi and inscriptions. Beyond it, the bare brick halls of the baths hold the museum's collections, and the height of the ruined walls, rising in open sky above the gardens, is a reminder of what a public building meant in the late empire.

Getting there

The baths stand in the Esquilino district in the centre of Rome, on Piazza della Repubblica and beside Roma Termini, the city's main railway station. Ciampino Airport (CIA) is about 14 km away.

Plan your visit

We have no confirmed visit data yet. Once it is confirmed, this block also carries the date it was checked.

From the encyclopaedia

The Baths of Diocletian were public baths in ancient Rome. Named after emperor Diocletian and built from AD 298 to 306, they were the largest of the imperial baths. The project was originally commissioned by Maximian upon his return to Rome in the autumn of 298 and was continued after his and Diocletian's abdication under Constantius, father of Constantine.

Wikipedia · CC BY-SA 4.0

Interesting facts

Why it is worth it

Getting there

Plan your visit

On these lists

From the encyclopaedia