Greenwich Tunnel

The Greenwich foot tunnel is a pedestrian tunnel crossing beneath the River Thames in East London, linking Greenwich (Royal Borough of Greenwich) in the south with the Isle of Dogs (London Borough of Tower Hamlets) to the north. The tunnel is currently open while refurbishment works continue on the entrance shafts and domes. The works were due to be complete by June 2011, but delays mean that they are now scheduled to be complete some time in 2012.

The Wikipedia page is http://en.wikipedia.org/wiki/Greenwich_foot_tunnel]