Why Is the Old City Below the New One?

A place with several lives

At The Liberty site in London’s Southwark, MOLA archaeologists recorded 2,959 layers and features. Their investigation traced changing uses across more than 2,000 years: Roman activity, burial, medieval fields and later buildings. Those features are not 2,959 separate cities stacked underground. They are pieces of a complicated history. ^[1]

Read the ground

Layers can accumulate as sediment arrives and people alter a place. In an undisturbed sequence, material underneath generally predates what lies above it. Archaeologists call the study of these layers stratigraphy. ^[2]

But real ground is messy. A later pit can cut into an older layer; digging and rebuilding can move earlier material. Depth alone cannot tell the whole story.

Next time you pass construction work in an old town, imagine its exposed ground as a partly shuffled archive. The important question is how its pieces fit together, rather than simply how far down they lie.