Caracalla - The Baths of Caracalla: the building

The Baths of Caracalla: the building

In 211 AD Caracalla drew up the plan for his famous baths in Rome, with architects and artists (there is no reason whatsoever to think that it was an idea of his father, as is often stated). The entire building measured 337 x 328 m., the core 220 x 114 m. Next to the central building two exedrae flank a large garden, that was adorned with statues and fountains.

The baths were plundered and excavated on numerous occasions. In the 11th and 12th century capitals were used in the Duomo of Pisa and the Basilica of S. Maria in Trastevere. Works of art are today scattered over museums.

Reconstructed plan of the Baths of Caracalla.
Image: Wikimedia, Sailko.

A detailed analysis of the brick stamps by Herbert Bloch has shown that work was not begun before 212 AD. The core of the baths was inaugurated in 216 AD, while the building was finished by Elagabalus and Alexander Severus, adding the porticos. The baths were fed by a branch of the Aqua Marcia, called by late sources a separate Aqua Antoni(ni)ana. An inscription on the Porta Tiburtina, a gate located on a spot where three aqueducts meet, documents the work on the aqueduct by Caracalla in the years 212-213 AD.

IMP(erator) CAES(ar) M(arcus) AVRELLIVS ANTONINVS PIVS FELIX AVG(ustus) PARTH(icus) MAXIM(us)
BRIT(annicus) MAXIMVS PONTIFEX MAXIMVS
AQVAM MARCIAM VARIIS KASIBVS IMPEDITAM PVRGATO FONTE EXCISIS ET PERFORATIS
MONTIBVS RESTITVTA FORMA ADQVISITO ETIAM FONTE NOVO ANTONINIANO
IN SACRAM VRBEM SVAM PERDVCENDAM CVRAVIT Emperor Caesar Marcus Aurellius Antoninus Pius Felix Augustus, Parthicus Maximus,
Britannicus Maximus, Pontifex Maximus,
saw to it that the Aqua Marcia, disrupted by various problems, after cleaning up the source, cutting through and piercing
mountains, with a restored channel and also the addition of a new Antoninian source,
was conducted to his sacred city.

Inscription on the Porta Tiburtina. EDR105389. 212-213 AD.

The Porta Tiburtina with the inscription from 212-213 AD.
Photo: Wikimedia, Joris van Rooden.

The aqueduct was supported by the older so-called Arch of Drusus.

The Arch of Drusus, supporting the Aqua Antoniniana.
Photo: Wikimedia, Rabax63.

Janet DeLaine has investigated the effort in erecting this gigantic building, "one of the largest single building projects ever undertaken in the city": the required raw materials, their transport, and the size of the labour force. Thousands of people must have been involved directly or indirectly with the raising and finishing of the baths. After the inauguration, fuel and olive oil for cleaning the body were required in large quantities on a daily basis.

There has been much discussion about a room called cella solearis, mentioned in the Historia Augusta: "Among his works at Rome he left the magnificent Baths which bear his name, the cella solearis of which architects say cannot be imitated in terms of construction. For it is said that lattices either of bronze or of copper were placed over (under) it, to which the whole vault is entrusted, and the span is so great that experienced engineers say it could not have been done" (translation Janet DeLaine). The correct reading must be cella soliaris, as found in several inscriptions in baths in North Africa. The word soliaris seems to be related to hot pools, solium being a bathtub. The room referred to must be the large round caldarium in the centre of the complex (between the core and the garden), now completely collapsed, the vault of which spanned 36 meters.

The core of the baths on Bing maps. The round caldarium - cella soliaris is in the lower left corner.

Written sources for the Baths of Caracalla
... thermas magnificentissimas fecerit. Caracalla built the most splendid baths. Historia Augusta, Septimius Severus 21,11.

Opera Romae reliquit thermas nominis sui eximias, quarum cellam soliarem architecti negant posse ulla imitatione qua facta est fieri. Nam et ex aere vel cupro cancelli subterpositi esse dicuntur, quibus cameratio tota concredita est, et tantum est spatii, ut id ipsum fieri negent potuisse docti mechanis. Idem viam novam munivit, quae est sub eius thermis, Antoninianis scilicet, qua pulchrius inter Romanas plateas non facile quicquam invenias. Among the public works which [Caracalla] left at Rome was the notable Bath named after himself, the cella soliaris of which, so the architects declare, cannot be reproduced in the way in which it was built by him. For it is said that the whole vaulting rested on gratings of bronze or copper, placed underneath it, but such is its size, that those who are versed in mechanics declare that it could not have been built in this way. He also constructed a new street at the side of his bath (that is to say, the Antonine Bath), and you will not easily find anything more beautiful among the streets of Rome. Historia Augusta, Caracalla 9,4-5 and 9.

... aucta urbs magno accessu viae novae et ad lavandum absoluta opera pulchri cultus. Caracalla endowed the city with the important access that is the via nova and very luxurious thermal baths. Aurelius Victor, Liber de Caesaribus 21,4.

Opus Romae egregium fecit lavacri, quae thermae Antoninianae appellantur. Caracalla erected a bath of excellent construction at Rome, which is called the bath of Antoninus. Eutropius, Breviarium ab Urbe condita 8,20.

Hoc imp. thermae Antoninianae dedicatae sunt. While Caracalla was ruling the Antonine baths were dedicated. Chronograph of 354 (Calendar of Filocalus), Imperia Caesarum.

Sabinus II et Venustus. His conss. Antoninus Romae thermas sui nominis aedificavit. Sabinus II and Venustus [216 AD]. Under these consuls Antoninus built the baths that bear his name at Rome. Cassiodorus, Chronica, Imperatores romani xviii.

Opera publica ipsius praeter ... lavacrum in vico Sulpicio, quod Antoninus Severi filius coeperat, nulla exstant. Et lavacrum quidem Antoninus Caracallus dedicaverat et lavando et populum admittendo, sed porticus defuerant, quae postea ab hoc subditicio Antonino exstructae sunt, ab Alexandro perfectae. No public works of Elagabalus are in existence, save ... the public bath in the Vicus Sulpicius, begun by Antoninus, the son of Severus. This bath, in fact, had been dedicated by Antoninus Caracalla, who bathed in it himself and opened it to the public, but the portico was left unbuilt, and this was added after his death by this spurious Antoninus, though actually completed by Alexander. Historia Augusta, Elagabalus 17,8-9.

Antonini Caracalli thermas additis porticibus perfecit et ornavit. The Baths of Antoninus Caracalla Alexander Severus completed and beautified by the addition of a portico. Historia Augusta, Alexander Severus 25,6.

Porticus termarum Antoniniarum arserunt et fabricatum est. [Aurelianus]. The portico of the Antonine baths caught fire and was rebuilt. Chronograph of 354 (Calendar of Filocalus), Imperia Caesarum.

αι δε Αντωνιαναι ουτω καλουμεναι εις χρειαν των λουομεων καθεδρας ειχον παρακειμενας χιλιας εξακοσιας, εκ μαρμαρου κατεσκευασμενας ξεστου. The baths that are called Antoniana had 1600 seats made of polished marble for convenient use by the bathers. Olympiodorus of Thebes, History fragment 43.

Aqua Antoniana; Aqua Antoniniana. Aqua Antoniana; Aqua Antoniniana. Polemius Silvius, Laterculus, Quae sint Romae (Th. Mommsen, Monumenta Germaniae Historica, Berlin 1892, Chronica minora, vol. 9,.1, p. 545); Notitia and Curiosum, Appendices.

IMP(erator) CAES(ar) M(arcus) AVRELLIVS ANTONINVS PIVS FELIX AVG(ustus) PARTH(icus) MAXIM(us) BRIT(annicus) MAXIMVS PONTIFEX MAXIMVS AQVAM MARCIAM VARIIS KASIBVS IMPEDITAM PVRGATO FONTE EXCISIS ET PERFORATIS MONTIBVS RESTITVTA FORMA ADQVISITO ETIAM FONTE NOVO ANTONINIANO IN SACRAM VRBEM SVAM PERDVCENDAM CVRAVIT	Emperor Caesar Marcus Aurellius Antoninus Pius Felix Augustus, Parthicus Maximus, Britannicus Maximus, Pontifex Maximus, saw to it that the Aqua Marcia, disrupted by various problems, after cleaning up the source, cutting through and piercing mountains, with a restored channel and also the addition of a new Antoninian source, was conducted to his sacred city.
Inscription on the Porta Tiburtina. EDR105389. 212-213 AD.

Written sources for the Baths of Caracalla
... thermas magnificentissimas fecerit.	Caracalla built the most splendid baths.	Historia Augusta, Septimius Severus 21,11.
Opera Romae reliquit thermas nominis sui eximias, quarum cellam soliarem architecti negant posse ulla imitatione qua facta est fieri. Nam et ex aere vel cupro cancelli subterpositi esse dicuntur, quibus cameratio tota concredita est, et tantum est spatii, ut id ipsum fieri negent potuisse docti mechanis. Idem viam novam munivit, quae est sub eius thermis, Antoninianis scilicet, qua pulchrius inter Romanas plateas non facile quicquam invenias.	Among the public works which [Caracalla] left at Rome was the notable Bath named after himself, the cella soliaris of which, so the architects declare, cannot be reproduced in the way in which it was built by him. For it is said that the whole vaulting rested on gratings of bronze or copper, placed underneath it, but such is its size, that those who are versed in mechanics declare that it could not have been built in this way. He also constructed a new street at the side of his bath (that is to say, the Antonine Bath), and you will not easily find anything more beautiful among the streets of Rome.	Historia Augusta, Caracalla 9,4-5 and 9.
... aucta urbs magno accessu viae novae et ad lavandum absoluta opera pulchri cultus.	Caracalla endowed the city with the important access that is the via nova and very luxurious thermal baths.	Aurelius Victor, Liber de Caesaribus 21,4.
Opus Romae egregium fecit lavacri, quae thermae Antoninianae appellantur.	Caracalla erected a bath of excellent construction at Rome, which is called the bath of Antoninus.	Eutropius, Breviarium ab Urbe condita 8,20.
Hoc imp. thermae Antoninianae dedicatae sunt.	While Caracalla was ruling the Antonine baths were dedicated.	Chronograph of 354 (Calendar of Filocalus), Imperia Caesarum.
Sabinus II et Venustus. His conss. Antoninus Romae thermas sui nominis aedificavit.	Sabinus II and Venustus [216 AD]. Under these consuls Antoninus built the baths that bear his name at Rome.	Cassiodorus, Chronica, Imperatores romani xviii.
Opera publica ipsius praeter ... lavacrum in vico Sulpicio, quod Antoninus Severi filius coeperat, nulla exstant. Et lavacrum quidem Antoninus Caracallus dedicaverat et lavando et populum admittendo, sed porticus defuerant, quae postea ab hoc subditicio Antonino exstructae sunt, ab Alexandro perfectae.	No public works of Elagabalus are in existence, save ... the public bath in the Vicus Sulpicius, begun by Antoninus, the son of Severus. This bath, in fact, had been dedicated by Antoninus Caracalla, who bathed in it himself and opened it to the public, but the portico was left unbuilt, and this was added after his death by this spurious Antoninus, though actually completed by Alexander.	Historia Augusta, Elagabalus 17,8-9.
Antonini Caracalli thermas additis porticibus perfecit et ornavit.	The Baths of Antoninus Caracalla Alexander Severus completed and beautified by the addition of a portico.	Historia Augusta, Alexander Severus 25,6.
Porticus termarum Antoniniarum arserunt et fabricatum est.	[Aurelianus]. The portico of the Antonine baths caught fire and was rebuilt.	Chronograph of 354 (Calendar of Filocalus), Imperia Caesarum.
αι δε Αντωνιαναι ουτω καλουμεναι εις χρειαν των λουομεων καθεδρας ειχον παρακειμενας χιλιας εξακοσιας, εκ μαρμαρου κατεσκευασμενας ξεστου.	The baths that are called Antoniana had 1600 seats made of polished marble for convenient use by the bathers.	Olympiodorus of Thebes, History fragment 43.
Aqua Antoniana; Aqua Antoniniana.	Aqua Antoniana; Aqua Antoniniana.	Polemius Silvius, Laterculus, Quae sint Romae (Th. Mommsen, Monumenta Germaniae Historica, Berlin 1892, Chronica minora, vol. 9,.1, p. 545); Notitia and Curiosum, Appendices.