Why is so much of the Colosseum missing?

Why it matters

The Colosseum is the structure most visitors picture when they picture Rome. It stands in the low valley between the Caelian, Esquiline, and Palatine hills, just east of the Roman Forum, and it is the largest amphitheater ever built and the largest one still standing anywhere. Construction began under the emperor Vespasian in 72 and was completed under his son and heir Titus in AD 80, with further changes made under Domitian. Because all three emperors belonged to the Flavian family, later scholars named it the Flavian Amphitheater.

It was built for spectacle: gladiatorial combat, animal hunts, executions, and reenactments of battles and myths. It could hold an estimated fifty thousand to eighty thousand spectators at different points in its history, with an average audience of around sixty-five thousand, and it served that purpose into the early Middle Ages.

Visitors often arrive expecting a complete ring and find something else: one tall curved wall of pale stone, and behind it a jagged inner structure that looks like a shell with its skin peeled away. That impression is accurate. Most of what is gone did not vanish in antiquity but across the centuries afterward, through earthquake, salvage, and the ordinary need for building stone.

Nero's lake, an emperor's gesture

The site was chosen deliberately. After the Great Fire of 64, Nero took much of this valley for his own palace, the Domus Aurea, and laid out an artificial lake surrounded by pavilions and gardens, with a giant bronze statue of himself at the entrance, a monument to his own reign rather than to the city.

Vespasian had most of the palace torn down and the lake filled in, and put the new amphitheater on the spot. Returning land an emperor had taken for himself to the public was a populist gesture, and it placed the building, unlike most amphitheaters, in the middle of the city.

A reconstructed inscription found on the site records that Vespasian paid for the work from his general's share of the spoils of the Jewish war that ended with the siege of Jerusalem in 70. The name Colosseum came much later, believed to come from that colossal statue of Nero, which Hadrian moved beside the amphitheater; by about the year 1000 the Latin name was in use for the building itself.

What you see from the outside

The Colosseum is free-standing, an ellipse about 615 feet long and 510 feet wide, and its outer wall rises 157 feet. The travertine blocks were laid without mortar and held with some 300 tons of iron clamps. When the clamps were pried out in the Middle Ages, they left the pockmarks that scar the stone today.

Only the north side of the original outer wall still stands. It shows the whole design: three stories of arcades framed by engaged columns in the three orders, Doric at the bottom, then Ionic, then Corinthian, with a tall attic above decorated with Corinthian pilasters and pierced by small windows. Most of what visitors walk around elsewhere is in fact the original inner wall, exposed when the outer ring fell.

At each end of the standing section, triangular brick wedges lean against the stone. They are not Roman: they were built in 1807 and 1827 to shore the wall up. The south side, on softer ground, collapsed in the great earthquake of 1349, and its stone was carted off to build palaces, churches, and hospitals across the city.

Inside: the tiers and the arena

The seating reflected Roman society rank by rank. The emperor and the Vestal Virgins had boxes at the north and south ends, with the best views. Senators sat on a broad podium beside them and brought their own chairs; the names of some fifth-century senators are still carved into the stone.

Above them came the knights, then ordinary citizens, with the rich seated below and the poor above, and at the very top a gallery for the poor, slaves, and women, who stood or found space on steep wooden benches, farthest from the action and most exposed to sun and weather.

The arena measured about 272 feet by 157 feet, a wooden floor covered in sand, and the Latin word for sand, harena, is where the word arena comes from. Little of the original floor survives. A section has been rebuilt, which lets visitors stand at arena level and look up at the tiers.

The hypogeum

Under the arena floor lies the hypogeum, the underground. It was not part of the first building: Domitian ordered it added. Its two levels of tunnels and cages held gladiators and animals before the games, and eighty vertical shafts, fitted with elevators, pulleys, and hinged platforms, lifted animals and scenery straight into the arena.

Tunnels connected the hypogeum to stables and to the gladiators' barracks at the Ludus Magnus to the east, and separate passages let the emperor and the Vestals come and go without crossing the crowds, a layout that still shapes the pattern of corridors a visitor can trace below the arena floor.

The underground passages were opened to the public in the summer of 2010, and since 2017 the top two levels of the building have been offered as guided routes as well. Check the park's own site and the booking ahead page for how these routes are organized and how to reserve a place.

After the games

By the late sixth century a small chapel had been built into the structure, and the arena itself had become a cemetery. The vaults under the seating were rented out as houses and workshops into the twelfth century, a long stretch of ordinary urban life inside an ancient ruined monument.

Around 1200 the Frangipani family fortified the building as a castle. A religious confraternity lived in its northern part from 1377 until the early nineteenth century, while the rest was quarried for stone and its marble burned down to make lime, the ordinary fate of much of the stone now missing from the site.

In 1749 Pope Benedict XIV forbade further use of the building as a quarry and consecrated it to the Passion of Christ, installing the Stations of the Cross. Later popes cleared the plants that had overgrown it and began the repairs that have continued since, and the first full cleaning and repair of the façade in the building's history was completed in 2016.

How to visit

The Colosseum, the Roman Forum, and the Palatine Hill belong to one archaeological park, and its online tickets are sold only on the park's own ticketing website, which also runs a form for reporting resale on unauthorized channels. Buy there rather than from resellers, and check which areas a given ticket covers, since the arena floor, the underground, and the upper levels are sold as separate routes.

Tickets carry the visitor's name, and the park allows a name to be changed only once, in a few listed cases and no later than the seventh day before the visit, so enter names carefully when booking. The booking ahead page covers the other timed tickets needed elsewhere in the city.

Allow at least an hour and a half for the building alone, more if the underground is added. The Arch of Constantine stands just to the southwest, on the old triumphal route, and the Forum and the Palatine are a few minutes' walk away, so the three are usually seen together in a long morning. Much of the park is exposed to the sun and its paths are uneven stone, so wear sturdy shoes and bring water.