Woolwich Foot Tunnel

The Woolwich Foot Tunnel runs 504 metres under the River Thames, from Old Woolwich on the south bank to North Woolwich on the north side. It was designed by Sir Maurice Fitzmaurice for the London County Council and opened on 26 October 1912. Both domed entrance buildings are Grade II-listed; the south one, tucked behind the old Waterfront leisure centre, is the oldest surviving building on Old Woolwich's riverside. Inside, lifts and spiral staircases lead down to a long, white-tiled tube, and at its deepest the roof is only about three metres below the river bed. It's open 24 hours, a free alternative to the Woolwich Ferry, and around a thousand people use it each day. Cycling isn't allowed inside, so cyclists walk their bikes through.