Israeli archaeologists have stumbled upon the mother of all garbage dumps: a massive landfill from early Roman times that may have been the result of the most sophisticated trash collection system in antiquity.

Layer upon layer of waste that was efficiently collected, piled up and buried some 2,000 years ago has been dug up on the slopes of the Kidron valley, just outside the Roman-era walls of Jerusalem.

Coins and fragments of pottery show the landfill was in use for about seven decades, from the beginning of the first century CE until the period of the Great Jewish Revolt against the Romans, which ended with the destruction of Jerusalem in 70 CE, says Yuval Gadot, a Tel Aviv University archaeologist who led the dig.

The landfill, which was excavated in 2013-2014 in conjunction with the Israel Antiquities Authority, rose to a towering 70 meters in height, from the bottom of the valley to the walls of the city. It was quite unusual in its size, Gadot says.

It seems uncommon, he says. "If you look at history, usually people don’t do that. They usually lived with their garbage, or they used it at some point, or it just sat out there in the street,” he says.

Going back thousands of years before the Roman era, as far back as the Neolithic, humans would dig pits for their garbage. They might collect it for later use as fertilizer, or use it to level terrain when constructing new buildings – both practices are still done today. But ancient examples of large-scale collection and long-term storage of trash in a landfill are scarce, Gadot says.

Down the drain in Rome

Beyond Jerusalem, across the rest of the Roman Empire, garbage disposal was a chronic problem, especially in large cities.

Rome has the Monte Testaccio, an artificial mound still visible today made up of millions of fragments of discarded amphorae. In this case, it isn't that the pottery pieces were collected from around the city – this was where the adjacent port on the River Tiber dumped trash.

In Rome and Pompeii, trash was sometimes disposed of in the sewage system, which was commonly used to get rid of anything undesirable. Even the bodies of the third-century emperor Heliogabalus, who was murdered by his guards, and of the Christian martyr Saint Sebastian were dumped in Rome’s main sewer, the Cloaca Maxima.

But most of the domestic trash was simply thrown into the street, usually after dark and with little regard for passersby, so much that the satirical poet Juvenal remarked that one should always make a will before going out for dinner, “because different forms of death can rain down from any open window.”

When a young and ambitious Vespasian – later an efficient administrator, ruthless repressor of the Jewish Revolt and emperor – was in charge of city maintenance, he failed so spectacularly to clear the streets that, as punishment, the emperor Caligula (not the sanest of Roman rulers) had him covered in mud.

Thou shalt take out the trash

In Jerusalem, however, it seems that the system worked. The landfill located on the eastern slopes of the city is not just impressive for its size: its alternating layers of ancient trash and soil suggest there was a deliberate attempt to systematically cover the garbage to prevent smells and deter scavengers, Gadot says.

Open gallery view The dig of Jerusalem's Roman era landfill, covered in snow. Credit: Yonatan Adler

It isn't that the people of ancient Jerusalem organized to collectively and obediently throw their dross over the city walls. “It looks like there was a mechanism in place that cleared the streets, cleared the houses, using donkeys to collect and throw away the garbage,” Gadot speculates.

The system may have developed out of a combination of Roman administrative knowhow and a growing observance among Jews of religious purity norms, researchers theorize.

Jews in early Roman Jerusalem were obsessed with purity and impurity, as shown by the proliferation of mikvehs (ritual baths), the frequent use of stone vessels (which were believed to be impervious to impurity) and the near absence of imported pottery.

“It could be that it became a norm in Jerusalem that you have to take out the garbage, because it’s impure and has to be brought outside the city,” Gadot suggests. “It’s not the municipality saying so: God says so, and that makes it easier.”

Gadot hesitates to say whether Jerusalemites were the first in history to organize such a large-scale waste management system.

“I don’t know if it’s the first, but it’s unique,” he told Haaretz in a recent interview. “Maybe there’s another landfill in Rome that was for domestic use, but at the moment we don’t know about it.”

One problem is also that archaeologists usually prefer to excavate large, impressive ruins rather than mundane sites like garbage landfills.

Fish meals in a Jewish city

Most of the garbage in the landfill is leftovers from “a typical middle-class lunch or dinner at the time,” including animal bones, charred remains of grains, olive pits and wood from household ovens.

The picture that emerges is of a fairly wealthy city, with plenty of meat to go around and even fish brought in from distant locations like the Mediterranean and the Sea of Galilee.

According to Abra Spiciarich, a student whose MA thesis focused on the animal bones found in the landfill, the meat mostly came from goats, sheep, with a smaller proportion of cattle and chickens. This confirms that Jerusalem’s population was overwhelmingly Jewish at the time, given the complete absence of pig bones and the marks of kosher slaughtering found on many of the remains.

Archaeologists also found waste from the manufacture of glass and stone vessels, which were apparently made in small household workshops in the city.

But very few bronze and iron artifacts have been found, not because they weren't in use, but apparently, because they were being recycled.

“It seems that any material that they could recycle, they collected separately and it never reached the landfill. It was melted or reused,” Gadot says. “Maybe at the domestic level they sold scraps of metal to someone who specialized in that.”

A Roman mop-up operation?

Not everyone agrees with Gadot’s reading of the site.

“We really don’t know what caused this accumulation,” says Alon de Groot, an Israel Antiquities Archaeologist who has participated in excavations in the area just above the landfill.

That neighborhood, today known as the City of David, is considered the oldest part of the city and its original nucleus. De Groot noted that the area was destroyed when the Romans captured Jerusalem at the end of the revolt. Later, they used the ruined buildings as a quarry to reconstruct the city as a Roman settlement called Aelia Capitolina.

Open gallery view The ancient City of David, Jerusalem: When Ezra reached Jerusalem, he read Torah to the people – but didn't mention Yom Kippur. Credit: Olivier Fitoussi

“Then they just cleared up the whole hill, and as a result you find the garbage below, but this is not really garbage from that period: it’s mostly a result of the cleaning up of the area above after the city was destroyed,” de Groot told Haaretz in a telephone interview.

Gadot says he remains convinced that the site functioned as Jerusalem’s garbage dump, arguing that if parts of the ruined city had simply been pushed down the slope, archaeologists would have found at least a few large stones used in construction, instead of just tiny pieces of pottery, bones and organic residue.

Helena Roth, an archeobotanist on Gadot’s team, studied the charred remains of wood found in the landfill and compared them to samples taken from the destruction layers in the city itself. In the landfill she mostly found traces of olive and fig trees – which surrounded the city and probably provided a cheap source of fuel. In the city itself, she also found rare or imported materials like boxwood and Lebanese cedar, likely the remains of luxury furniture that was burned down with the rest of the city.

The fact that the dump and city had different wood remains supports the idea that the landfill functioned as a garbage storage site, Roth says.

The holiest garbage

Another comparative study conducted by the Tel Aviv team was with materials found about a decade ago in a smaller landfill from the same period, very near by - just under the Temple Mount.

There, a team led by archaeologists Guy Bar-Oz and Ronny Reich had found significant amounts of pigeon bones.

Because these birds were often used a sacrificial animal in ancient Israel, they speculated that this dump was used to collect the remains of the cultic activities that took place at the nearby Temple. Gadot says that no pigeon bones have been found in the city dump he excavated, strengthening the theory that what was found in the northern landfill by his colleagues was indeed “holy garbage.”

Click here for story: Pigeon meat is kosher.