ROME – The ancient amphitheater has lasted as an iconic landmark of Rome for almost  2,000 years. It survived the fall of the Roman Empire, countless invasions, World War II bombings and hordes of tourists, who regularly try to nip off pieces of it to take home as souvenirs.

The Colosseum, it has seemed, was just like the city of Rome: eternal.

But a careful and lengthy examination of its structural stability, carried out by Italian geologists, provided a damning verdict: the Colosseum is in fact slanting on one side by 16 inches, and might need urgent repairs before it starts leaning like the Tower of Pisa.  

Researchers at Rome's La Sapienza University and the environmental geology institute IGAG first noticed the anomaly one year ago. They now fear there may be a crack in the base below the amphitheater.

"The slab of concrete on which the Colosseum rests, which is like a 13 meter (42 foot) thick oval doughnut, may have a fracture inside it," Giorgio Monti, from La Sapienza's construction technology department, told Italy’s daily newspaper Corriere della Sera. 

The study will continue for another year, but critics are already taking note of the unruly and busy traffic that flows by just a few feet from the Colosseum on a daily basis.

The Colosseum sits in the middle of an important artery that connects the Roman Forum to the Circus Maximus. Tourists and Romans use it heavily, and have turned it into the biggest and most glorified roundabout in the world.  

Fabio Fumagalli, a research coordinator at La Sapienza University, said cars produce more damage than the nearby subway.

Alessandro Bianchi / Reuters

Tourists walk in front of Rome's ancient Colosseum on Monday. The ancient Colosseum of Rome, where gladiators fought for their lives, is slanting about 16 inches lower on the south side than on the north, and authorities are investigating whether it needs urgent repairs.

“Cars subject the monument to constant vibrations, and speed up its decay, while subway trains at least pass by with intervals of many minutes.”

News of the slanting monument re-ignited criticism over delays in long-planned renovation. There hasn’t been an overall refurbishing of the Colosseum in 73 years, and recent attempts by private sponsors to pay for its re-styling have been met with fierce resistance by government officials, who fought their bid as fiercely as the lions that once roamed in the arena.

Diego della Valle, the Italian designer behind the shoe brand Tod’s, offered to pay $34 million for a face-lift of the Colosseum in exchange for exclusive rights to its image for 15 years.

Despite the initial reluctance by the officials, who felt that selling off the monument to a shoemaker would make gladiators turn in their graves, the deal was finally granted for the sake of the monument.  

Since the beginning of the year, several stones have fallen off the Colosseum, proving it is in urgent need of repair. Following many delays the restoration works were set to start on July 31, but the date has already been moved once, this time to December.

If the Colosseum has been standing there for 2,080 years almost 2,000 years*, officials seem to reason, it can survive another few months.

Correction: Thanks for your comments. We stand corrected. The Colosseum was built around 70-80 AD (not B.C.) so it is almost 2,000 years old - not 2,080 years old. 

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