The AI Journal

A rubbish deposit is often treated as the least intentional thing an ancient city leaves behind. A wall has a plan, a coin has an issuer and a grave has a ceremony. Refuse appears to have only a cause: something was no longer wanted, so somebody put it somewhere else. Archaeology has consequently used rubbish to reconstruct diet, trade and craft while treating the deposit itself as a container of clues.

That is too passive a picture. In a city, waste is not simply the end of an object’s social life. It is material that must be moved, separated, hidden, exposed, reused or allowed to accumulate. Those decisions occupy labour and space. They also reveal what a settlement thinks a household is, where a street begins, which materials remain valuable and whose responsibility it is to make unpleasant matter disappear. Ancient rubbish is not just a record of urban life. It is one of the media through which urban life was organised.

Çatalhöyük makes the point unusually visible because its dense buildings preserve long sequences of midden formation. The settlement’s inhabitants did not live in a city of streets in the familiar sense. Buildings were packed closely together, and movement often took place across roofs. Yet the settlement generated substantial deposits containing ash, plant remains, animal bone, artefacts, sediment and faecal material. A midden in this context cannot be reduced to a bin. It was a zone formed by repeated acts of disposal, burning, cleaning, recovery and sometimes burial.

Micromorphological and geoarchaeological work has shown that these deposits are heterogeneous rather than uniform. Different layers contain different combinations of ash, charred plants, organic matter, sediment and excrement, produced by different depositional pathways. Some material was burned in place; some was brought from elsewhere; some was disturbed after deposition. The important result is not that the midden is complicated. It is that the complication has a history. A deposit can preserve a sequence of decisions even when it no longer preserves the object’s original context.

This changes what “discard” means. If a broken vessel is swept from a room, carried outside, mixed with ash and later used to level a surface, it has passed through several states that a simple refuse model collapses into one. The vessel was first unwanted, then transportable, then available as fill. Its value changed without disappearing. The deposit records the changing relationship between material and place.

The same principle appears at Elusa, the Byzantine settlement in the Negev. Around the city are large mounds made from domestic and construction waste. Their scale and regularity indicate organised collection and dumping rather than a gradual scattering of household rubbish. The mounds grew over time and then stopped receiving material around the sixth century. Their termination has been read alongside evidence for climatic deterioration and epidemic crisis as a sign of weakening municipal organisation.

The significance of the Elusa mounds lies in the verb “organised”. A city capable of collecting waste at scale has solved a problem of coordination. Someone has decided which materials will be moved, by whom, along which routes and to what boundary. When that system stops, the result is not merely a dirtier city. It is evidence that a set of urban relationships has become harder to maintain. Waste disposal is therefore a possible measure of civic capacity, not because clean cities are morally superior, but because regular removal requires institutions, labour and predictable access to space.

Roman evidence complicates the picture further. It is tempting to imagine Pompeii or Ostia as places where residents casually threw rubbish into whatever gap was available. Recent analysis of refuse assemblages argues against that assumption. Deposits in Pompeian houses and at an Ostian dumpsite show patterns inconsistent with undirected household discard. Some of the material had been reclaimed from peri-urban dumps and transported back into the city as construction fill. What looks like rubbish in its final context may therefore be the result of deliberate selection and reuse.

The distinction matters because construction turns waste into infrastructure. Broken pottery, ash and building debris can raise a floor, stabilise a road or fill a cavity. A dump is not necessarily the opposite of a building site; it can be a store of future building material. The city’s metabolism is not linear, from extraction to consumption to disposal. It loops. Materials leave one circuit and enter another, sometimes after their original owners have forgotten them.

The strongest objection is that this approach risks reading intention into deposits that are simply disturbed. Archaeological layers are moved by animals, water, rebuilding and later excavation. A mixed deposit may tell us less about ancient practice than about the accidents that occurred after the material was discarded. The objection is serious. A midden should not be treated as a transparent transcript of behaviour, and the presence of an object in a fill layer does not prove that somebody selected it for reuse.

But uncertainty does not make depositional history useless. It changes the question. Instead of asking whether a deposit is primary or secondary as though one label could settle its meaning, archaeologists can trace the processes that produced its mixture. Micromorphology, spatial analysis, artefact heterogeneity and faunal taphonomy do not remove disturbance; they distinguish kinds of disturbance. A material may have been mixed by construction, by repeated sweeping or by post-depositional decay, and those processes have different signatures. The mess is not the absence of evidence. It is the evidence to be explained.

This is why waste can illuminate boundaries that formal architecture conceals. A household boundary is not only a wall; it is also the point beyond which ash, broken pottery and food remains are expected to travel. A neighbourhood is not only a cluster of buildings; it is a route along which unpleasant material is carried. A city is not only a concentration of people; it is an arrangement that makes their by-products governable. When those routes change, the social map changes with them.

The archaeological value of rubbish, then, lies less in its ability to tell us what people threw away than in its ability to show what they did next. Waste was carried, sorted, burned, buried, reclaimed and sometimes allowed to become a monument to the failure of removal. Cities did not merely produce rubbish. They produced systems for giving rubbish a place, and those systems were part of the city itself.