Rome Has a Hill Made of Fifty-Three Million Broken Jars

On the south side of Rome, between the Aventine Hill and the Tiber, there is a hill that should not exist. It stands about thirty-five meters high and runs roughly seven hundred meters around at the base, and it looks, from a distance, like any other unbuilt slope in the city — scrubby grass, dust, a fence. The neighborhood around it is called Testaccio, and on a Friday night it is one of the livelier corners of Rome: there are restaurants and clubs cut into the base of the hill itself, their back walls formed by the material the hill is made of.

Because the hill is not made of earth. From base to summit, all the way through, Monte Testaccio is made of broken pottery.

Specifically, it is made of one kind of broken pottery: the large, thick-walled, roughly spherical amphora in which Spanish olive oil was shipped across the Mediterranean during the Roman Empire, each jar holding about seventy liters. The jars arrived at Rome's river wharves full, were emptied into the city's supply, and then had a problem that decided their fate: oil soaks into coarse ceramic and turns rancid, and a container that taints its next cargo is worth less than nothing. Wine amphorae could be reused. Oil amphorae could not. So the empties were carried a short distance from the wharves, smashed, and stacked.

Somebody engineered this dump

Stacked is the correct word, and it is the first genuinely strange thing about the hill. This was not a tip that things were flung onto. Excavation has shown that the sherds lie in ordered courses: the bodies of the jars were broken into large curved plates and laid flat, the necks and handles were used to level each course and shore up the edges, and the layers were dusted with lime as they went up, to keep down the smell of rancid oil residue. Retaining walls built of whole and half amphorae hold the flanks. Somebody laid this landfill out. Somebody managed its growth, kept crews working on it, and ran it as a public facility, in continuous operation, for roughly a century and a half — from the second century into the earlier third.

Then there is the count. The mound's outer dimensions are real measurements, surveyed many times, and they give a volume of around 580,000 cubic meters. Divide that by the space one broken, compacted amphora occupies once it has been smashed for stacking and settled under the weight of everything above it, and the result comes out at roughly fifty-three million containers. Nobody has tallied fifty-three million sherds — that figure is a modern reconstruction, not a count, and it is honest to say so. But the mound itself is not in dispute. You can stand on it.

Fifty-three million jars, laid end to end at about a meter each, would stretch more than fifty thousand kilometers — farther than the circumference of the earth. Every one of them was made, filled, loaded, shipped, unloaded, emptied, and carried to the hill by hand.

The dump that can be read

A hill of that size would be remarkable purely as a fact about scale. What makes Monte Testaccio one of the most important archaeological sites in the Roman world is something smaller: a great many of the sherds carry writing.

Before an oil amphora left Spain, officials and merchants painted inscriptions onto its neck and belly in black and red ink — the name of the shipper, the empty and full weights of the jar, the estate or district the oil came from, and a control notation added at inspection, recording that the contents had been checked, when, and by whom. Archaeologists call these painted labels tituli picti. On the sherds of Monte Testaccio, sheltered inside the mound for eighteen centuries, tens of thousands of them are still legible. A single broken jar can tell you who shipped it, what it weighed, where its contents were pressed, and the year an inspector signed off on it.

Multiply that by a hill, and the dump becomes something else entirely: a stratified, dated, self-documenting record of a single commodity trade, running for a hundred and fifty years. Consider what has actually been read out of it:

Family firms, across generations. The same shippers' names recur on sherds decades apart — fathers succeeded by sons, working the same Spanish river valleys, in a trade stable enough to be inherited.

A procedure built against fraud. The oil was weighed and certified at the point of shipment, by named officials, against declared weights painted on the jar. Someone in the Roman administration anticipated that shippers might cheat on weight, and built a paperwork routine to catch it — then painted that routine onto every jar, where it survives.

The state moving in. In the mound's later layers, the character of the inscriptions shifts, and the state's own stamp appears where private shippers' names once did — the visible trace, pressed into clay, of a trade being pulled from private contract toward public administration.

A calendar. Because the inspection notations carry dates, excavators have been able to map the mound's internal chronology and show that it grew in ordered, datable courses across its century and a half. The rubbish is stratified like a well-kept file.

Questions that historians would struggle to answer from any surviving text — how was a bulk commodity trade actually organized, audited, and policed? — turn out to be answerable from a garbage heap, one painted label at a time.

The city that made the hill necessary

The hill only makes sense against the city it served. At its height, in the first and second centuries, Rome held somewhere near a million people — the figure is contested, and honest methods disagree, but no serious estimate makes the city anything other than enormous beyond precedent, in a world where a large city meant something like fifty thousand people. The land around Rome could not feed a population of that size and the Romans never seriously tried to make it do so. The grain came by sea — from Sicily, then Africa, then above all Egypt — at a rate modern reconstructions put at roughly 200,000 metric tons a year, though the honest range runs from about 135,000 to 240,000 depending on the population figure and the consumption rate you start from.

Worked into pictures, that tonnage means something like two and a half to three and a half loaded ships arriving every day, on average, across a sailing season of about 230 days — every day the sea was open, for centuries. At the far end of the operation, roughly two hundred thousand registered citizens were entitled to collect five modii of grain — about 32.5 kilograms — every month, free of charge, under a state apparatus the Romans called the annona.

And alongside the grain came the oil. Spread Monte Testaccio's fifty-three million containers across its century and a half of active use and you get somewhere near 20,000 to 25,000 metric tons of olive oil a year passing through this one dump — a lower bound on the trade, since other container types carried oil too. The hill is what that trade left behind: not a monument anyone intended, but the packaging of a city's food supply, stacked in one place, labeled, and never moved.

That may be the strangest thing about Monte Testaccio. Rome is a city of deliberate monuments — arches, columns, and temples built to be remembered by. The hill was built by dock workers disposing of empties, and it has outlasted most of them. It was never meant to say anything, which is exactly why it can be trusted.

The hill is where my book Feeding Rome: The Grain Fleet, the Annona, and the Logistics of a Million-Person City begins. The book follows the food itself, from an Egyptian threshing floor to a Roman bakery — the tax collected in wheat, the ships and the winds, the hexagonal harbor at Portus, the barges towed up the Tiber, the warehouse districts, the mills and ovens, and the ration queue — and ends in the fifth century, when the supply was cut and the city discovered what its size had rested on all along. If a rubbish dump that turned out to be an archive sounds like your kind of history, the rest of the operation is just as well documented, and just as strange.