Temple of Claudius

The Arch of Dolabella and Silanus (Latin, Arcus Dolabellae et Silani) or Arch of Dolabella is an ancient Roman arch. It was built by senatorial decree in 10 AD by the consuls P. Cornelius Dolabella and C. Junius Silanus.

The Porta Caelimontana or Celimontana was a gate in the Servian Wall on the rise of the Caelian Hill (Caelius Mons).

The Colosseum ( KOL-ə-SEE-əm; Italian: Colosseo [kolosˈsɛːo]) is an oval amphitheatre in the centre of the city of Rome, Italy, just east of the Roman Forum. It is the largest ancient amphitheatre ever built, and is still the largest standing amphitheatre in the world today, despite its age. Construction began under the emperor Vespasian (r. 69–79 AD) in 72 and was completed in 80 AD under his successor and heir, Titus (r. 79–81). Further modifications were made during the reign of Domitian (r. 81–96). The three emperors that were patrons of the work are known as the Flavian dynasty, and the amphitheatre was named the Flavian Amphitheatre (Latin: Amphitheatrum Flavium; Italian: Anfiteatro Flavio [aɱfiteˈaːtro ˈflaːvjo]) by later classicists and archaeologists for its association with their family name (Flavius). The Colosseum is built of travertine limestone, tuff (volcanic rock), and brick-faced concrete. It could hold an estimated 50,000 to 80,000 spectators at various points in its history, having an average audience of some 65,000; it was used for gladiatorial contests and public spectacles including animal hunts, executions, re-enactments of famous battles, and dramas based on Roman mythology, and briefly mock sea battles. The building ceased to be used for entertainment in the early medieval era. It was later reused for such purposes as housing, workshops, quarters for a religious order, a fortress, a quarry, and a Christian shrine. Although substantially ruined because of earthquakes and stone-robbers (for spolia), the Colosseum is still an iconic symbol of Imperial Rome and was listed as one of the New7Wonders of the World. It is one of Rome's most popular tourist attractions and also has links to the Roman Catholic Church, as each Good Friday the Pope leads a torchlit "Way of the Cross" procession that starts in the area around the Colosseum. The Colosseum is depicted on the Italian version of the five-cent euro coin.

The historic district of Rome was declared World Heritage Site by the United Nations Educational, Scientific and Cultural Organization in 1980. It covers 19,91 km² and is included in 22 rioni with 186.802 inhabitants. There are 25.000 importants archaeological sites and locations.The 22 rioni are Monti, Trevi, Colonna, Campo Marzio, Ponte, Parione, Regola, Sant'Eustachio, Pigna, Campitelli, Sant'Angelo, Ripa, Trastevere, Borgo, Esquilino, Ludovisi, Sallustiano, Castro Pretorio, Celio, Testaccio, San Saba and Prati.

The Ludus Magnus (also known as the Great Gladiatorial Training School) was the largest of the gladiatorial schools in Rome. It was built by the emperor Domitian (r. 81–96 C.E.) in the late first century C.E., alongside other building projects undertaken by him such as three other gladiatorial schools across the Roman Empire. The training school is situated directly east of the Colosseum in the valley between the Esquiline and the Caelian hills, an area already occupied by Republican and Augustan structures. While there are remains that are visible today, they belong to a reconstruction that took place under the emperor Trajan (r. 98–117) where the Ludus plane was raised by about 1.5 metres (4 ft 11 in). The Ludus Magnus was essentially a gladiatorial arena where gladiators from across the Roman Empire would live, eat, and practice while undergoing gladiatorial training in preparation for fighting at the gladiatorial games held at the Colosseum.

The church of San Tommaso in Formis is a small church in Rome, situated on the Caelian Hill.

The Castra Peregrina ("camp of the strangers") was a castrum (a military barracks) in Rome situated on the Caelian Hill. It was occupied by various military units during the later part of the Roman Empire.

The Arch of Constantine (Italian: Arco di Costantino) is a triumphal arch in Rome dedicated to the emperor Constantine the Great. The arch was commissioned by the Roman Senate to commemorate Constantine's victory over Maxentius at the Battle of Milvian Bridge in AD 312. Situated between the Colosseum and the Palatine Hill, the arch spans the Via Triumphalis, the route taken by victorious military leaders when they entered the city in a triumphal procession. Dedicated in 315, it is the largest Roman triumphal arch, with overall dimensions of 21 m (69 ft) high, 25.9 m (85 ft) wide and 7.4 m (24 ft) deep. It has three bays, the central one being 11.5 m (38 ft) high and 6.5 m (21 ft) wide and the laterals 7.4 m (24 ft) by 3.4 m (11 ft) each. The arch is constructed of brick-faced concrete covered in marble. The three bay design with detached columns was first used for the Arch of Septimius Severus in the Roman Forum (which stands at the end of the triumph route) and repeated in several other arches now lost. Though dedicated to Constantine, much of the sculptural decoration consists of reliefs and statues removed from earlier triumphal monuments dedicated to Trajan (98–117), Hadrian (117–138) and Marcus Aurelius (161–180).

The Gay Street (Italian: Gay Street di Roma) is an area in Rome, Italy designated as a gay- and lesbian-friendly neighborhood. A 300-metre shopping and bar area in the center of the city on Via San Giovanni in Laterano, a street leading to the east flank of the Colosseum, it was formally designated in 2007. The opening ceremonies, led by the Italian LGBT organization Arcigay, were attended by celebrities and national and municipal politicians.

San Gregorio Magno al Celio, also known as San Gregorio al Celio or simply San Gregorio, is a church in Rome, Italy, which is part of a monastery of monks of the Camaldolese branch of the Benedictine Order. On March 10, 2012, the 1,000th anniversary of the founding of the Camaldolese in 1012 was celebrated here at a Vespers service attended by Anglican and Catholic prelates and jointly led by Pope Benedict XVI and Rowan Williams, Archbishop of Canterbury. San Gregorio is located on the Caelian Hill, in front of the Palatine. Next to the basilica and monastery is a convent of nuns and a homeless shelter run by Mother Teresa of Calcutta's congregation, the Missionaries of Charity.

The Villa Celimontana (previously known as Villa Mattei) is a villa on the Caelian Hill in Rome, best known for its gardens. Its grounds cover most of the valley between the Aventine Hill and the Caelian.

The Meta Sudans (Latin: "sweating turning post") was a large monumental conical fountain in ancient Rome.The Meta Sudans was built some time between 89 and 96 under the Flavian emperors, a few years after the completion of the nearby Colosseum. It was built between the Colosseum and the Temple of Venus and Roma, close to the later Arch of Constantine, at the juncture of four regions of ancient Rome: regions I, III, IV, X (and perhaps II).A meta was a tall conical object in a Roman circus that stood at either end of the central spina, around which racing chariots would turn. The Meta Sudans had the same shape, and also functioned as a similar kind of turning point, in that it marked the spot where a Roman triumphal procession would turn left from the via Triumphalis along the east side of the Palatine onto the via Sacra and into the Forum Romanum itself. The Meta Sudans was built of a brick and concrete core, faced with marble. It seems to have "sweated" the water (sudans means "sweating"), rather than jetting it out the top. This may mean that it oozed out the top, or perhaps that water came from holes in its side. The monument is estimated to have stood up to 17m high; until the 20th century, its concrete core was still over 9m high. It had a base pool 16m wide and 1.4m deep. The fountain was obviously damaged in the Middle Ages because it already appears as a ruin in early views of the Colosseum. Photos from the end of the 19th century show a conical structure of solid bricks next to the Arch of Constantine, surrounded by its own original, reflecting stone pool. The ruins of Meta Sudans survived until the 20th century. In 1936 Benito Mussolini had its remains wantonly demolished and paved over to make room for the new traffic circle around the Colosseum. A commemorative plaque was set in the road. Although the above-ground structure is gone, its foundations were later re-excavated, revealing the extensive substructure. After another excavation in 1997-98 the traffic circle was closed and the area became a pedestrian district.Extensive excavations directed by Clementina Panella of the University of Rome "La Sapienza" have revealed extensive archaeological information about the Meta Sudans and the northeast slope of the Palatine Hill.