BATHS OF DIOCLETIAN

The Baths of Diocletian, today occupying the area bounded by Via del Viminale, Piazza della Repubblica, Via Torino, Via Cernaia, Via Volturno and Via XX Settembre, were the largest bathing complex in ancient Rome.

Construction was begun by Emperor Maximian in AD 298 and completed between AD 305 and 306. The baths were dedicated to Diocletian, with whom Maximian shared the government of the Roman Empire. The complex covered an area of approximately 13 hectares and could accommodate up to 3,000 people at the same time.

The layout followed the model of the great imperial baths, with the main bathing rooms — the caldarium, tepidarium and frigidarium — arranged along a central axis. At the centre was the great natatio, an open-air swimming pool covering approximately 4,000 square metres, while the surrounding enclosure contained numerous other halls and rooms serving the various functions of the complex.

The overall structure of the Baths is still clearly recognizable today, despite the profound transformations it has undergone over the centuries.

The complex remained in use until the mid-6th century, when the Gothic War caused severe damage to the city and, in particular, disrupted the water supply essential to the operation of the baths.

REUSE

Santa Maria degli Angeli e dei Martiri and the Carthusian Monastery

After approximately a thousand years of abandonment, in 1561 Pope Pius IV assigned part of the ancient Baths for the construction of the Basilica of Santa Maria degli Angeli e dei Martiri and the Carthusian monastery. The project was entrusted to Michelangelo Buonarroti, who was then eighty-six years old.

Michelangelo worked on the great bathing halls, transforming the frigidarium, tepidarium and part of the natatio into the new space of the basilica. His design ingeniously adapted the existing Roman architecture to the needs of the new church, preserving much of its monumental structure.

For the Carthusian monastery, Michelangelo probably suggested the overall layout and prepared the design for the great cloister. Construction of the Great Cloister, now commonly known as the Cloister of Michelangelo, nevertheless began in 1565, one year after the artist’s death, and continued for several decades. It is therefore more accurate to describe the cloister as being based on Michelangelo’s design or project rather than as a work physically executed by him.

The Carthusian monastery followed the traditional layout of the order, with a larger cloister intended for the monks’ cells and enclosed life, and a smaller cloister serving communal functions such as the refectory and chapter house.

THE CLOISTER OF MICHELANGELO

Covering approximately 10,000 square metres, arranged around four wings each about 100 metres long and articulated by approximately 100 monolithic travertine columns, the Great Cloister is one of the largest in Italy. Construction, probably based on Michelangelo’s design, began in 1565; the upper level was not completed until 1676.

Today, numerous Roman sculptures, funerary stelae and sarcophagi are displayed along the four wings of the cloister and in the central garden. Originally conceived for the life of the Carthusian monastery, this vast space is now one of the most evocative areas of the Museo Nazionale Romano.

THE SMALL CLOISTER

The smaller cloister was created by occupying approximately one third of the ancient natatio, the Baths’ great swimming pool. At the centre of the courtyard stands a circular well made from reused ancient architectural elements.

The cloister, also known as the Ludovisi Cloister, housed works from the celebrated Boncompagni-Ludovisi collection for many years. These were subsequently transferred to Palazzo Altemps.

Olearie papali alle Terme di Diocleziano CC-BY-SA-3.0 via Wikimedia Commons

OCTAGONAL HALL (Planetarium)

The Octagonal Hall, probably originally used as a secondary bathing room, has a square exterior and an octagonal interior and is covered by a magnificent dome. In the 17th century, the building was converted into one of the warehouses of the papal grain supply system.

In 1928, the Octagonal Hall was converted into a planetarium, a function it retained until 1987, when the projector was removed. Today, the hall forms part of the Baths of Diocletian museum complex and is used for exhibitions and cultural activities.

THE ANNONA WAREHOUSES AND PAPAL OIL STORES

From the 16th century onwards, some of the rooms of the Baths were reused for functions connected with the food supply of Rome. From 1575, under Pope Gregory XIII, some of the structures were converted into granaries belonging to the papal Annona, and subsequently into oil storage facilities.

PIAZZA DELLA REPUBBLICA, FORMERLY PIAZZA DELL’ESSEDRA

The great semicircular exedra that formed one side of the Baths complex was preserved in the urban layout of modern Piazza della Repubblica, originally known as Piazza dell’Esedra.

The shape of the square follows that of the ancient Baths’ exedra and remains one of the most spectacular examples of the continuity between imperial Rome and the modern city.

San Bernardo alle Terme – ceiling By Livioandronico2013

SAN BERNARDO ALLE TERME

One of the two large circular halls located on either side of the exedra was converted into the Church of San Bernardo alle Terme in 1598. The building retains its characteristic circular shape, with a diameter of approximately 22 metres, and is covered by a dome with an oculus.

With its distinctive form recalling some of the great buildings of Roman architecture, the church is one of the most interesting examples of the reuse of the ancient Baths in the modern city of Rome.

MUSEO NAZIONALE ROMANO – BATHS OF DIOCLETIAN

The Museo Nazionale Romano was established in 1889 with the aim of collecting and preserving antiquities from Rome and its surrounding territory. The Baths of Diocletian are the museum’s historic headquarters and house an extraordinary collection of archaeological finds, including sculptures, inscriptions, funerary objects and works discovered during excavations carried out in Rome.

The Baths and the Carthusian monastery were gradually adapted for use as a museum. The archaeological restoration of the ancient spaces received a major boost on the occasion of the International Exhibition of 1911 and continued in the following decades.

From the 1990s onwards, the Museo Nazionale Romano was organized into four locations: the Baths of Diocletian, Palazzo Massimo, Palazzo Altemps and Crypta Balbi.

The Baths site now includes important sections devoted to the Protohistory of the Latin Peoples and Written Communication in the Roman World, as well as numerous sculptures, funerary artefacts and architectural elements. The museum route also includes the magnificent Cloister of Michelangelo, where hundreds of works are displayed.

The surviving ancient bathing halls themselves form an essential part of the visit and are also used for temporary exhibitions.

CREDITS
Museo Nazionale Romano – Baths of Diocletian; Italian Ministry of Culture; General Catalogue of Cultural Heritage.