The floor of the colosseum, where you might expect to see a smooth ellipse of sand, is instead a bewildering array of masonry walls shaped in concentric rings, whorls and chambers, like a huge thumbprint.
The confusion is compounded as you descend a long stairway at the eastern end of the stadium and enter ruins that were hidden beneath a wooden floor during the nearly five centuries the arena was in use, beginning with its inauguration in A.D. 80.
Weeds grow waist-high between flagstones; caper and fig trees sprout from dank walls, which are a patchwork of travertine slabs, tufa blocks and brickwork. The walls and the floor bear numerous slots, grooves and abrasions, obviously made with great care, but for purposes that you can only guess.
The guesswork ends when you meet Heinz-Jürgen Beste of the German Archaeological Institute in Rome, the leading authority on the hypogeum, the extraordinary, long-neglected ruins beneath the Colosseum floor.
Best has spent much of the past 14 years deciphering the hypogeum—from the Greek word for “underground”—and this past September I stood with him in the heart of the great labyrinth.
See where a semicircular slice has been chipped out of the wall?” he said, resting a hand on the brickwork. The groove, he added, created room for the four arms of a cross-shaped, vertical winch called a capstan, which men would push as they walked in a circle.
The capstan post rested in a hole that Beste indicated with his toe. “A team of workmen at the capstan could raise a cage with a bear, leopard or lion inside into position just below the level of the arena. Nothing bigger than a lion would have fit.” He pointed out a diagonal slot angling down from the top of the wall to where the cage would have hung.
“A wooden ramp slid into that slot, allowing the animal to climb from the cage straight into the arena,” he said
Just then, a workman walked above our heads, across a section of the arena floor that Colosseum officials reconstructed a decade ago to give some sense of how the stadium looked in its heyday, when gladiators fought to their death for the public’s entertainment.
The footfalls were surprisingly loud. Beste glanced up, then smiled. “Can you imagine how a few elephants must have sounded?”
Today, many people can imagine this for themselves. Following a $1.4 million renovation project, the hypogeum was opened to the public this past October.
Trained as an architect specializing in historic buildings and knowledgeable about Greek and Roman archaeology, Beste might be best described as a forensic engineer.
Reconstructing the complex machinery that once existed under the Colosseum floor by examining the hypogeum’s skeletal remains, he has demonstrated the system’s creativity and precision, as well as its central role in the grandiose spectacles of imperial Rome.
When Beste and a team of German and Italian archaeolgists first began exploring the hypogeum, in 1996, he was baffled by the intricacy and sheer size of its structures: “I understood why this site had never been properly analyzed before then. Its complexity was downright horrifying.”
The disarray reflected some 1,500 years of neglect and haphazard construction projects, layered one upon another. After the last gladiatorial spectacles were held in the sixth century, Romans quarried stones from the Colosseum, which slowly succumbed to earthquakes and gravity.
Down through the centuries, people filled the hypogeum with dirt and rubble, planted vegetable gardens, stored hay and dumped animal dung. In the amphitheater above, the enormous vaulted passages sheltered cobblers, blacksmiths, priests, glue-makers and money-changers, not to mention a fortress of the Frangipane, 12th-century warlords.
By then, local legends and pilgrim guidebooks described the crumbling ring of the amphitheater’s walls as a former temple to the sun. Necromancers went there at night to summon demons.
In the late 16th century, Pope Sixtus V, the builder of Renaissance Rome, tried to transform the Colosseum into a wool factory, with workshops on the arena floor and living quarters in the upper stories. But owing to the tremendous cost, the project was abandoned after he died in 1590.
In the years that followed, the Colosseum became a popular destination for botanists due to the variety of plant life that had taken root among the ruins. As early as 1643, naturalists began compiling detailed catalogs of the flora, listing 337 different species.
By the early 19th century, the hypogeum’s floor lay buried under some 40 feet of earth, and all memory of its function—or even its existence—had been obliterated. In 1813 and 1874, archaeological excavations attempting to reach it were stymied by flooding groundwater.
Finally, under Benito Mussolini’s glorification of Classical Rome in the 1930s, workers cleared the hypogeum of earth for good.
Beste and his colleagues spent four years using measuring tapes, plumb lines, spirit levels and generous quantities of paper and pencils to produce technical drawings of the entire hypogeum.
“Today we’d probably use a laser scanner for this work, but if we did, we’d miss the fuller understanding that old-fashioned draftsmanship with pencil and paper gives you,” Beste says. “When you do this slow, stubborn drawing, you’re so focused that what you see goes deep into the brain. Gradually, as you work, the image of how things were takes shape in your subconscious.”
Unraveling the site’s tangled history, Beste identified four major building phases and numerous modifications over nearly 400 years of continuous use. Colosseum architects made some changes to allow new methods of stagecraft. Other changes were accidental; a fire sparked by lightning in A.D. 217 gutted the stadium and sent huge blocks of travertine plunging into the hypogeum.
Beste also began to decipher the odd marks and incisions in the masonry, having had a solid grounding in Roman mechanical engineering from excavations in southern Italy, where he learned about catapults and other Roman war machines. He also studied the cranes that the Romans used to move large objects, such as 18-foot-tall marble blocks.
By applying his knowledge to eyewitness accounts of the Colosseum’s games, Beste was able to engage in some deductive reverse engineering.
Paired vertical channels that he found in certain walls, for example, seemed likely to be tracks for guiding cages or other compartments between the hypogeum and the arena.
He’d been working at the site for about a year before he realized that the distinctive semicircular slices in the walls near the vertical channels were likely made to leave space for the revolving bars of large capstans that powered the lifting and lowering of cages and platforms.
Then other archaeological elements fell into place, such as the holes in the floor, some with smooth bronze collars, for the capstan shafts, and the diagonal indentations for ramps.
There were also square mortises that had held horizontal beams, which supported both the capstans and the flooring between the upper and lower stories of the hypogeum.
Here, too, the hypogeum’s powerful lifts, hidden ramps and other mechanisms were critical to the illusion-making. “Rocks have crept along,” Martial wrote, “and, marvelous sight! A wood, such as the grove of the Hesperides [nymphs who guarded the mythical golden apples] is believed to have been, has run.”
Following the executions came the main event: the gladiators. While attendants prepared the ritual whips, fire and rods to punish poor or unwilling fighters, the combatants warmed up until the editor gave the signal for the actual battle to begin. Some gladiators belonged to specific classes, each with its own equipment, fighting style and traditional opponents.
For example, the retiarius (or “net man”) with his heavy net, trident and dagger often fought against a secutor (“follower”) wielding a sword and wearing a helmet with a face mask that left only his eyes exposed.
Contestants adhered to rules enforced by a referee; if a warrior conceded defeat, typically by raising his left index finger, his fate was decided by the editor, with the vociferous help of the crowd, who shouted “Missus!” (“Dismissal!”) at those who had fought bravely, and “Iugula, verbera, ure!” (“Slit his throat, beat, burn!”) at those they thought deserved death.
Gladiators who received a literal thumbs down were expected to take a finishing blow from their opponents unflinchingly.
The winning gladiator collected prizes that might include a palm of victory, cash and a crown for special valor. Because the emperor himself was often the host of the games, everything had to run smoothly.
The Roman historian and biographer Suetonius wrote that if technicians botched a spectacle, the emperor Claudius might send them into the arena: “ would for trivial and hasty reasons match others, even of the carpenters, the assistants and men of that class, if any automatic device or pageant, or anything else of the kind, had not worked well.” Or, as Beste puts it, “The emperor threw this big party, and wanted the catering to go smoothly.
If it did not, the caterers sometimes had to pay the price.”
To spectators, the stadium was a microcosm of the empire, and its games a re-enactment of their foundation myths. The killed wild animals symbolized how Rome had conquered wild, far-flung lands and subjugated Nature itself. The executions dramatized the remorseless force of justice that annihilated enemies of the state. The gladiator embodied the cardinal Roman quality of virtus, or manliness, whether as victor or as vanquished awaiting the deathblow with Stoic dignity.
“We know that it was horrible,” says Mary Beard, a classical historian at Cambridge University, “but at the same time people were watching myth re-enacted in a way that was vivid, in your face and terribly affecting. This was theater, cinema, illusion and reality, all bound into one.”