How Deep Does London Go?

By M@

Last Updated 06 February 2024

How Deep Does London Go?

The tube network is just one of many subterranean spaces in London. With sewers, water pipes, bunkers, basements, and assorted other tunnels, it's a maze down there. We've attempted to summarise some of these systems in one diagram, including the yet-to-be-built Thames Tideway sewer tunnel.

The graphic shows typical depths below surface level (or high-tide level for the Thames foot tunnels). Where depth is variable, we've shown the average as a horizontal stretch of tunnel, plunging down to the deepest point. For example, the tube varies greatly in depth, but is typically 24m. The deepest point is below Hampstead Heath at Bull and Bush (where a station was part-built, but never completed), which reaches 67m.

The deepest space in London is the recently completed Lee Tunnel, a relief sewer that slopes down to 80m beneath Beckton.

Find out more about subterranean London

Naturally, our graphic is only scratching the surface, so to speak. We've left off several road tunnels, tram tunnels, service tunnels and plenty of bunkers, for the sake of clarity.

With thanks to the Crossrail press team and engineers for a few hard-to-find details.