Baths of Caracalla

The baths were raised on the Piccolo Aventino, beside the first stretch of the Via Appia about 400 metres beyond the ancient Porta Capena, on ground that had been the horti Asiniani, a garden estate developed by Gaius Asinius Pollio in the reign of Augustus. Caracalla appropriated Pollio's estate for the work. The buildings already standing there were pulled down, in some cases to their ground floors, filled in with earth and built into the foundations of the new complex. One of them, a two-storey noble domus put up between 134 and 138 in the reign of Hadrian and partly demolished in 206, was excavated first by Francesco Ficoroni in the mid-18th century and again by G. B. Guidi in 1860–67, and has since been opened to the public.

Brick stamps place the fabric between 212 and 216, and the baths were inaugurated in 216, five years after Caracalla came to the throne. The work was probably begun by his father Septimius Severus; one account puts the start as early as 206, a dating that has been criticised. Water was brought by a branch of the Aqua Marcia created in 212 and named the Aqua Antoniniana, which crossed the Via Appia on the existing Arch of Drusus and ended in the cisterns on the south-west side. Access was by the Via Nova, a broad and probably tree-lined road; the Severan family commissioned that road and the Septizodium on the nearby Palatine Hill in the same quarter.

For the work to have been mostly finished in Caracalla's own reign, the labourers would have had to lay more than 2,000 tonnes of material every day for six years. Decoration went on after his death under his successors Elagabalus, who reigned from 218 to 222, and Severus Alexander, who reigned to 235; both concerned themselves with the outer precinct, and the baths were probably largely complete by 235.

The baths were free and open to the public, heated by a hypocaust that burned coal and wood beneath the floors to warm water fed in by the dedicated aqueduct. They served chiefly the residents of the first, second and twelfth Augustan regions, the tract between the Caelian, the Aventine and the Circus Maximus. Olympiodorus of Thebes gives a capacity of 1,600, taken to mean the number of bathers who could use the complex at any one time, against a daily figure thought to have been 6,000 to 8,000. They were the most imposing public baths built anywhere in the Roman empire until the Baths of Diocletian were inaugurated in 306.

Repairs followed under Aurelian, after a fire, and under Diocletian; Constantine the Great altered the caldarium, and further work is recorded under Theodosius and last of all under the Gothic king Theodoric, who ruled from 493 to 526. Writing in the fifth century, Polemius Silvius counted the baths among the seven wonders of Rome, famous for the richness of their decoration, and they were still fully working at that date. Around the middle of the fourth century a Christian pilgrimage site called the titulus Fasciolae had grown up close by, near the church of Santi Nereo e Achilleo, and the water supply of the baths became useful to pilgrims and to the church community.

In 537, during the Gothic War, Vitiges, king of the Ostrogoths, laid siege to Rome and severed the city's water supply. The baths stopped working and were abandoned shortly afterwards. Lying too far from the still-populated part of the city, they were mostly left alone, though in the sixth and seventh centuries they were apparently used for the burial of pilgrims who had died after being cared for in the nearby xenodochium of Santi Nereo e Achilleo, and simple tombs of that period have been found inside the bath area. Popes Adrian I, Sergius II and Nicholas I may have had some work done on the aqueduct during the ninth century. The earthquake of 847 destroyed much of the building, along with many other Roman structures.

From at least the 12th century the ruins were worked as a quarry, both for plain building material and for decorative pieces to be reused in churches and palaces; Pisa Cathedral and Santa Maria in Trastevere both contain architectural elements taken from the bath site, and kilns stood nearby for burning fine marble down into lime. During the 14th century the area was given over to vineyards and gardens, farmed on behalf of the owners of neighbouring villas and of ecclesiastical bodies and associations. In the 15th century Pope Pius II took stone from the baths for the Loggia of the Benediction at St Peter's Basilica.

In 1524 Pope Clement VII granted Cardinal Lorenzo Pucci a licence to remove unlimited quantities of columns, marble, travertine and other ancient stone for a palace the cardinal was building near St Peter's. Under Clement's successor Paul III, excavations between 1545 and 1547 uncovered large statues in marble and bronze together with innumerable architectural fragments, lamps, intaglios and cameos, in such quantity that a museum, the Museo Farnese, was created to hold the collection; it was moved to the Real Museo Borbonico late in the 18th century, and many of the Farnese pieces took the road to Naples through inheritance and dynastic succession. The Farnese Bull, probably from the eastern palaestra, and the Farnese Hercules, from the frigidarium, are now in the national archaeological museum there. Paul III granted the area itself to the Roman Seminary of the Jesuits, and it was used as a playground for children; Philip Neri may have brought children here from his oratory, and is believed to have commissioned the fresco of the Madonna supported by an angel that is still in the natatio.

The last whole granite column was taken out of the natatio in 1563 and given by Pope Pius IV to Cosimo I de' Medici, first Grand Duke of Tuscany, who set it in the centre of Piazza Santa Trinita in Florence, where it became the Column of Justice. Two granite tubs from the frigidarium went to Piazza Farnese and were worked into fountains by Girolamo Rainaldi. Substantial architectural decoration was still standing in these years, recorded in drawings by Andrea Palladio, Giovanni Antonio Dosio and Antonio da Sangallo the Elder, and later by Giovanni Battista Falda, Giambattista Nolli and Giuliano da Sangallo.

In 1824 Count Egidio di Velo dug at the baths and found the mosaics of athletes now in the Vatican Museums, a polychrome pavement carrying twenty-eight figures. Luigi Canina worked in the frigidarium until the middle of the century, and Battista Guidi from 1860 to 1867. Restoration in the central part of the complex between 1866 and 1869 revealed a torso of Hercules, porphyry columns and figure-adorned capitals.

In 1870 the area became the property of the Italian government, and Pietro Rosa conducted excavations in the eastern palaestra; in 1878–9 Giuseppe Fiorelli discovered mosaics in the caldarium and the western palaestra. From the early 20th century the work spread outwards and downwards into the subterranean passages, which were cleared in 1901 and 1912 and again in 1938. Those campaigns opened up the mithraeum, the largest found in Rome, which can be dated only by the events either side of it: it was made after the complex was completed around 217 and was probably out of use once the aqueduct was cut in the 530s. Most scholars read the pit in its floor as a fossa sanguinis, over which the bull of the Mithraic story was killed and initiates bathed in its blood, though others take it for a stage trapdoor.

A statue of Aphrodite Anadyomene came out of a nearby room in 1912 and is now in the Museo Nazionale Romano at the Baths of Diocletian. Excavation from the same year uncovered an underground water mill; first taken for medieval, it is now considered ancient, and fire damage shows it burned in the third century and was rebuilt with alterations. Of the restorations carried out on the eastern side in the late 1930s, when an opera stage was installed in the caldarium, no documentation survives beyond a few sketches.

From 1937 the central part of the complex was used for open-air concerts and theatrical performances, and above all for the summer season of the Rome Opera, which made its home in the caldarium. The season ran without interruption apart from the war years until 1993, when it stopped and the site was restored and stripped of the fixed structures added for the shows. The area served as the circuit for the Rome Grand Prix four times between 1947 and 1951, and the gymnastics events of the 1960 Summer Olympics were held here. In 1990 the baths were the venue and backdrop for the first Three Tenors concert.

Restoration in the 1980s cleared away thick vegetation and illegally built houses and repaired the southern wall with its cisterns, the south-western library and the octagonal hall known as the Temple of Jupiter. The opera stage was dismantled in 1998–9, modern visitor facilities were added, and the baths reopened to the public in 2001. Opera came back to a temporary movable stage set outside the main structure, on ground less critical archaeologically and with less stress on the ancient fabric, the audience cut to 3,500 seats from the 8,000 of the old arrangement.

The baths were the only archaeological site in Rome damaged by the earthquake near L'Aquila on 6 April 2009, and took minor damage again in the central Italian earthquake of August 2016. That year the museum circuit joining the baths to the tomb of Cecilia Metella and the Villa dei Quintili was the twenty-sixth most visited state site in Italy, with 268,449 visitors and gross takings of €947,556. The site is protected as Italian national heritage and run as a state museum under the Italian culture ministry, open for an admission fee with access limited to certain areas and walkways so that the mosaic floors are not further damaged. In 2024, after eighteen centuries, water flowed again at the baths through a new mirror pool placed at the entrance.