The Baths of Diocletian, the largest in the ancient world, are the historical premises of the Museo Nazionale Romano.
Established in 1889 as one of the principal centers of historical and artistic culture of a united Italy, the museum was intended to preserve and exhibit the works of historical collections passed to the state and the numerous antiquities that were found in the course of the work of adapting Rome to its new role as the Capital of the Kingdom of Italy. The museum’s purpose was to increase the city’s historical and artistic heritage and contribute with it in the most effective way to fostering culture. About a century after its establishment in the Baths of Diocletian, the Museum was reorganized with four distinct locations, with Palazzo Massimo, Palazzo Altemps and the Crypta Balbi being added to the Baths.
The Baths of Diocletian were built in just eight years, between 298 and 306 AD, on a site between the Viminal and Quirinal hills. They covered an area of over 13 hectares. They were surrounded by a large wall and an imposing exedra with steps, corresponding to today’s Piazza della Repubblica. On either side of the exedra there were two libraries set side by side at the edge of the wall, with two circular rooms, one transformed in 1598 into the church of S. Bernardo, the other still visible at the beginning of Via del Viminale.
The principal rooms, the frigidarium, tepidarium and calidarium, were laid out in sequence along a central axis, at the sides of which, symmetrically arranged, were all the other rooms: next to the frigidarium there were two large open-air palaestrae (or gymnasiums). Aligned with the calidarium were two octagonal rooms, one of which was used between 1928 and the 1980s as a Planetarium.
The complex was restored at the beginning of the 5th century and probably remained in use for a few more decades. After lying derelict for almost a thousand years, in 1561 Pope Pius IV decided to build a basilica inside the Baths with a Carthusian monastery attached to it dedicated to the Madonna degli Angeli and the memory of the Christian martyrs who, according to legend, had died during the construction of the Baths. The project was entrusted to Michelangelo. He respected the ancient building, using the frigidarium and the tepidarium without altering their features, and devised the great Cloister. In the same years the small cloister was also built (called the Ludovisi Cloister after the collection of ancient sculptures that it long housed, now in Palazzo Altemps), adjacent to the presbytery of the church, which occupies about a third of the great pool (natatio) of the Baths.
In 1575, under Gregory XIII, the great halls of the baths were transformed into granaries and warehouses for olive oil.
The Great Halls of the Baths of Diocletian
Room VIII hosts some of the magnificent architectural fragments of the Baths. Through a prospect lined by pillars and columns, the room faced the natatio, with part of its monumental façade now visible. The pool covered some 4,000 square meters. The façade, whose restoration has brought out its architectural articulation, was designed on the model of the fixed scenery in a theater, with three orders of columns framing niches containing statues. Its surface was covered with colored marbles and mosaics creating extraordinary polychrome effects.
Room X was one of the entrances to the central body of the Baths. On display here is the so-called Platorini sepulcher, discovered in 1880 on the right bank of the Tiber. It is important to remember that the remains discovered in Rome and its suburbs have been brought together in the Museo delle Terme di Diocleziano. For this reason two chamber tombs set inside a large core of tuff (volcanic stone) are also exhibited here. They were excavated in 1951 on the Via Portuense. In the niches of this room there are statues of men in togas and women in drapery, of unknown provenance, but probably from funerary settings.
Room XI was used as the reservoir of water supplying the thermae. It currently displays a large black and white mosaic dating from the 2nd century AD. Found in 1931 in the archaeological area of Nero’s villa at Anzio, it measures about 80 square meters. In the center, among elegant volutes, Hercules is portrayed victoriously holding the horn he has just torn from the bleeding head of the river god Achelous.
Photo credit: Museo Nazionale Romano