BBC London Travel
The original Blackwall Tunnel, opened in 1897
From Sunday 7 February drivers won't be able to travel south through the Blackwall Tunnel overnight as the 112-year-old northbound tunnel is given a facelift.
The Tunnel will close Sundays to Thursdays between 2100 and 0500 GMT. There will also be occasional closures on Friday nights.
Transport for London has a long list of upgrades planned for the tunnel including ventilation, replacing lights and improving drainage. It hopes to complete the work by December 2012.
When the tunnel is closed, northbound traffic will use the remaining, newer tunnel with all southbound traffic diverted via other river crossings such as Tower Bridge, the Rotherhithe Tunnel or the Dartford crossings.
The Rotherhithe Tunnel will close every Friday night from midnight to 0700 GMT.
The aging tunnel
The northbound Blackwall Tunnel is 112 years old and at the time of opening in 1897 was the longest underwater crossing in the world.
More than 50,000 vehicles pass through the tunnel every day, and TfL says the upgrade is necessary to bring it in line with European safety regulations.
Bus route 108
The only bus to run through the Blackwall Tunnel, the 108, will inevitably be disrupted.
There will be no late evening service through the Tunnel between 2100 and 0100 GMT on Monday to Thursday nights, and between 2100 and midnight GMT on Sundays.
The bus will then be escorted through the tunnel every half hour between 1am and 5am.
During these times the 108 will run in two sections: Stratford to Canning Town (via Poplar) and North Greenwich to Lewisham (via Blackheath)
The last through bus from Lewisham will be at 2027 GMT (2034 on Sunday). The last through bus from Stratford will be at 2031 GMT.
There will be no connection across the river towards Lewisham between 0015 and 0045 GMT.
Buses will run normally on Friday and Saturday nights. Passengers can use bus tickets on the Jubilee line between North Greenwich and Canning Town while the tunnel is closed.