Urban archaeology

Urban archaeology is a sub discipline of archaeology specialising in the material past of towns and cities where long-term human habitation has often left a rich record of the past.

Humans produce waste: Large concentrations of humans produce large concentrations of waste. Kitchen waste, broken objects, and similar material all need to be disposed of. Small numbers of people can dispose of their waste locally without encouraging vermin or endangering their health. Once people began to live together in large numbers, around five thousand years ago, such methods began to become impractical. Material would be brought into these new settlements but would rarely be taken out again.

Up until the nineteenth century when organised rubbish disposal became widespread in urban areas people invariably threw their waste from their windows or buried it in their gardens. If their houses fell down, a common enough occurrence when planning laws were non-existent, owners would pick out what they could reuse, stamp down the remains and rebuild on the old site.

The effect of this is that even a moderately sized settlement of any antiquity is built on top of a heap of refuse and demolished buildings and is therefore raised up from its original height on a plateau of archaeology. This is most apparent in the tel sites of the Near East where towns that have been occupied for thousands of years are raised up many metres above the surrounding landscape.

In walled towns such as those in medieval Europe the effect of the encircling defences was to hold in the waste so that it could not slip outwards, magnifying the effect.

Archaeological excavation within historic cities therefore often produces a thick stratigraphy dating back to the original foundation and telling the story of its history.

The City of London serves as an example, for urban excavations have been performed there since the late 1900s. These excavations, performed in populated areas of the city, revealed historical evidence of events unforeseen previously by historians. London sits on a tel, which preserves a layer of dark material, attributed to the burning of the city by Boudica in 60 AD. It was only by excavation of the urban areas that these revelations could be made, as the city has long since outgrown its borders after its rebuild, some years after the Boudican revolt.

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