Thousands of people in ancient Rome watched enslaved men, convicted criminals and untamed animals battle in a large amphitheater known as the Colosseum. To make these gruesome displays possible, Roman architects and engineers designed an elaborate set of tunnels below the arena's wooden floor.
Once the Roman Empire collapsed in 476 A.D., almost two-thirds of the Colosseum—including the network of subterranean chambers, also known as the hypogeum—fell into a state of disrepair. But in 2018 experts began renovating the hidden system of passageways, so tourists would be able to roam where gladiators and wild animals once prepared for combat.
As Angela Giuffrida reports for the Guardian, officials unveiled the newly renovated hypogeum in a ceremony last Friday. Now, the public can walk through 525 feet of wooden walkways for the first time in the Colosseum’s 2,000-year-old history. This unveiling follows the two-year, $29.8 million restoration project, which was initially funded by the Italian fashion company Tod’s, writes Artnet News.
“Today we are returning to the public a monument within a monument,” says Alfonsina Russo, director of the Colosseum and its archaeological park, as quoted by the Guardian. “What emerged [from the project] is that the hypogeum had a 400-year-long history, from when the amphitheater opened in AD80 to the final show in 523.”
A group of nearly 80 experts, including archaeologists, architects, conservators, engineers and geologists were involved in the restoration effort, according to Artnet News. As CNN’s Hada Messia points out, the team used a combination of photographic surveys, surface mapping and cleaning techniques, which removed grime, algae and lichen from the structure’s surfaces.
During the restoration process, experts also uncovered a wealth of archaeological data about the amphitheater’s history, from the time it opened in 80 A.D. to the final games, which took place in 523 A.D., writes the New York Times’ Elisabetta Povoledo.
Speaking with the Times, Russo says, “The [structure's] transformations often followed the tastes of the various emperors." And added that the restoration “was a very complex effort.”
Experts cleaned the Colosseum’s façade and replaced some of the metal gates near ground-level arches in the first and second stages of the restoration. In the latter phases, restorers fixed sections of the hypogeum, refurbished the galleries on the second level and moved the services center outside the arena, per the Times.
“We want to give an idea of how it was, and we are seeking proposals from around the world,” Russo told the Times’ Tom Kington in a 2020 article.
As Artnet News points out, Romans began constructing the Colosseum in 72 A.D. during Emperor Vespasian’s reign and finished it almost eight years later. At the height of its popularity, the venue could host between 50,000 and 70,000 people, and for 450 years, the structure was the site of animal hunts, theatrical shows, gladiatorial contests, executions and other events, per CNN.
When Romans used the arena, the hypogeum looked like a “huge sailing ship,” noted Tom Mueller for Smithsonian magazine in 2011. The tunnels also contained several ropes and other apparatuses to lift the gladiators and animals above ground.
“The hypogeum allowed the organizers of the games to create surprises and build suspense,” Heinz-Jürgen Beste, a researcher at the German Archaeological Institute in Rome, told Smithsonian in 2011. “A hunter in the arena wouldn’t know where the next lion would appear, or whether two or three lions might emerge instead of just one.”
Though experts have finished restoring the hypogeum, officials still plan to renovate other parts of the arena’s structure. In May, the Ministry of Culture announced that it will construct a wooden stadium that will sit above the hypogeum and people will be able to use the newly refurbished space to host concerts and other cultural events, according to CNN.
“It is time to restart—to move forward—because there is a lot of work to be done,” says Tod's CEO Della Valle at the unveiling ceremony, as quoted by CNN.