Located in the south and southwest of Rome, Caelian Hill (Mons Caelius) is one of the largest of the original Seven Hills of Rome.
Location
Located in the ancient city’s south, the Caelian Hill measures approximately two kilometers (1.2 mi) long and an average of 450 (0.25 mi) wide.
The western bank of the hill ended near the Palatine Hill. The eastern end met up with the Esquiline Hill in what was an important junction for several of the city’s aqueducts.
Due to its location, little was to be seen on the southern and eastern sides of the hill, as the Aurelian Wall bordered both sides.
Looking north from the hill, one would see several sites. Most of the northern bank of the hill sat opposite the Esquiline Hill and its ‘spur,’ the Oppian Hill.
Some of the most prominent structures north of the Caelian Hill include the Colosseum, the Ludus Magnus, Moneta Caesaris (Imperial mint), and the Temple of Isis. The Baths of Titus and Trajan can also be spotted on the Esquiline Hill.
Looking northwest, one would see the Temple of Venus and Roma, the Arch of Constantine, and the Temple of Apollo. The Palatine Hill also sat northwest of the Caelian Hill. Here, we will see the Imperial Palaces, Domitian Palace, and the Palatine Stadium.
Turning west, we would be able to spot the Circus Maximus in the distance (with the Aventine Hill on the opposite side of that), while the Septizodium (also known as the Septizonium) was located much closer to the Caelian. The Porta Capena (the gate in which the Via Appia originally started) is located close to the western bank of the hill.
The major structure southwest of Caelian Hill is the Baths of Caracalla. The nearby Aqua Antoniniana supplied the baths with water.
The Porta Metronia was located directly south of the Caelian Hill.
As for the hill itself, there were many structures built upon it.
The Servian Wall had been built on the hill, effectively cutting it in half. The Wall in this part of the city had two gates associated with it – the Porta Caelimontana located on the southeastern bank of the hill and the Porta Querquetulana on the hill itself, but closer to the northern bank at the mid-point of the hill. Earlier scholarship had the names of these gates switched with each other.
Apart from the Porta Metronia located south of the hill, the construction of the Aurelian Wall introduced two more gates to the Caelian—the Porta Asinaria on the southern bank and the Porta Praenestina on the eastern side.
The most recognizable structure on the Caelian Hill was the Temple of Claudius, located on the northwestern tip of the hill, directly opposite the Colosseum.
Other structures that were located on the Caelian Hill include the Castra Peregrina, Macellum Magnum, Domus Lateranorum, Baths of Helena (Thermae Helenae), Amphiteatrum Castrense, Castra Nova Equitum Singularium, and the Aqua Claudia (which included the extension Arcus Neroniani that covered the Caelian Hill).
History
According to ancient sources, the Caelian Hill was named after an Etruscan general, Caeles Vibenna, who aided Rome in a time of need.
One of the oldest sources that survives in modern times is the book On the Latin Language by Marcus Terentius Varro. In it, he directly attributes the naming of the hill to Vibenna. In Book V, XLVI he writes:
“In the section of the Suburan region, the first shrine is located on the Caelian Hill, named from Caeles Vibenna, a Tuscan leader of distinction, who is said to have cone with his followers to help Romulus against King Tatius.”
This story is confirmed by the historian Tacitus in his book, Annals. The person’s name is correct, but the events surrounding Vibenna’s rise to prominence are seemingly disputed. He adds that the hill went by another named before it was known as Caelian Hill. Book IV, LXV:
“It may not be out of place to state that the hill was originally named the “Querquetulanus,” from the abundance of oak produced on it, and only later took the title of “Caelius” from Caeles Vibenna, an Etruscan chief, who, for marching to the aid of Rome, had received the district as a settlement, either from Tarquinius Priscus or by the gift of another of our kings. On that point, the authors disagree: the rest is not in doubt — that Vibenna’s numerous forces established themselves on the level also, and in the neighborhood of the forum, with the result that the Tuscan Street has taken its name from the immigrants.”
In Varro’s version, Vibenna came to the aid of Rome’s first King, Romulus, against King Tatius of the Sabines. However, in Tacitus’ version, Vibenna was given the land possibly by Tarquinius Priscus, who was Rome’s fifth King. However, Tacitus does leave open the possibility that another King (such as Romulus) granted Vibenna land on the hill.
(This is one of the challenges when researching and writing about ancient history. As the events are so old and much of the information has been lost to history, it can be challenging to piece together what happened. Many events occurred at a time when there weren’t a lot of records kept. It’s still a fascinating endeavor to undertake!!).
Another point of conjecture surrounds the incorporation of the Caelian Hill into Rome itself. Three contemporaries, Livy, Strabo, and Dionysius of Halicarnassus claim that different people were responsible for incorporating the hill into the burgeoning kingdom.
Livy states that Rome’s third king, Tullus Hostilius, was responsible for expanding Rome’s borders to include the Caelian Hill. He also moved there to encourage others to live there as well. In his book, The History of Rome, Book I, XXX.I, he writes:
“Rome, meanwhile, was increased by Alba’s downfall. The number of citizens was doubled, the Caelian Hill was added to the City, and, that it might be more thickly settled, Tullus chose it for the site of the king’s house and from that time onwards resided there“
However, according to Strabo, it was Hostilius’ successor, Ancus Marcius, who included the hill into the kingdom. In his book, Geography, Book V, III.VII, he writes:
“The first founders walled the Capitolium and the Palatium and the Quirinal Hill, which last was so easy for outsiders to ascend that Titus Tatius took it at the first onset, making his attack at the time when he came to avenge the outrage of the seizure of the maidens. Again, Ancus Marcius took in Mt. Caelium and Mt. Aventine and the plain between them, which were separated both from one another and from the parts that were already walled.”
Meanwhile, Dionysius of Halicarnassus believes that it was incorporated much earlier, noting that it was, in fact, Rome’s founder, Romulus, who added the hill to Roman lands. In his book, Roman Antiquities, Book II, L.I, he notes:
“Romulus and Tatius immediately enlarged the city by adding to it two other hills, the Quirinal, as it is called, and the Caelian; and separating their habitations, each of them had his particular place of residence. Romulus occupied the Palatine and Caelian hills, the latter being next to the Palatine, and Tatius the Capitoline hill, which he had seized in the beginning, and the Quirinal.”
The Caelian Hill was featured prominently in the great fire of AD 64, starting nearby in the Circus Maximus before ravaging large portions of the city before coming to a halt at the foot of the Esquiline Hill. Tacitus recounts what happened during those tumultuous days in his book, Annals. Book XV, XXXVIII.I:
“There followed a disaster, whether due to chance or to the malice of the sovereign is uncertain — for each version has its sponsors — but graver and more terrible than any other which has befallen this city by the ravages of fire. It took its rise in the part of the Circus touching the Palatine and Caelian Hills, where, among the shops packed with inflammable goods, the conflagration broke out, gathered strength in the same moment, and, impelled by the wind, swept the full length of the Circus: for there were neither mansions screened by boundary walls, nor temples surrounded by stone enclosures, nor obstructions of any description, to bar its progress. The flames, which in full career overran the level districts first, then shot up to the heights, and sank again to harry the lower parts, kept ahead of all remedial measures, the mischief traveling fast, and the town being an easy prey owing to the narrow, twisting lanes and formless streets typical of old Rome.”
The Temple of Claudius was the most prominent structure on the Caelian Hill in Roman times. It underwent some changes, even within the first few decades of its construction. Thanks to Rodolfo Lanciani’s writings, we can understand the Temple’s early life while noting that it was unclear when it finally collapsed.
In his book, The Ruins and Excavations of Ancient Rome: A Companion Book for Students and Travelers (1897), he briefly explains the Temple named after the fourth Roman Emperor. Page CCCL-CCCLI:
‘Begun by Agrippina the younger, niece and fourth wife of that Emperor. After the murder of Agrippina, which took place in AD 59, Nero, her son, took possession of the unfinished temple and turned it into a nymphaeum and reservoir for the Aqua Claudia, joining it to the main aqueduct “ad Spem verterum (Porta Maggiore) by means of the Arcus Caelimontani or Arcus Neroiani, which still forms so conspicuous a feature of the Caelian Hill. After the suicide of Nero, AD 68, the place was restored to its original use by Vespasian under the name of “Templum divi Claudii’, which the people shortened into that of Claudium. A bull of Honorius III, dated February 2, 1217, shows that the classic term was still in use in the thirteenth century (Clodeum). The causes and the date of its final collapse are not known”.
The hill was also the site of the revolt by the workers in the Imperial mint in AD 271, while it suffered greatly in Alaric’s Sack of Rome in AD 410. Many churches were built in the area over the centuries, some of which still stand today.
What is now on the Caelian Hill?
Besides Roman ruins, we have many structures located on the Caelian Hill. There are plenty of churches, including the Basilica of Saints John and Paul, the Basilica of Saint Stephen, the Church of San Tommaso in Formis, the Lateran Palace, and the Lateran Obelisk. Many of these churches were built during Roman times, with some being built atop older Roman temples.
Sources:
On the Latin Language – Marcus Terentius Varro
Annals – Tacitus (Thayer)
The History of Rome – Livy (Perseus Digital Library)
Geography – Strabo (Thayer)
Roman Antiquities – Dionysius of Halicarnassus (Thayer)
The Ruins and Excavations of Ancient Rome – Rodolfo Lanciani