Rush hour commuters are being asked not to get on the Northern Line between Tooting Bec and Clapham North - because TfL say it's just too busy.
The pilot project, which starts on Monday, will see TfL offering advice on alternative routes and asking commuters to walk or cycle instead of boarding trains on the line between 0800 and 0845 on weekday mornings.
The scheme follows similar tactics adopted during the Olympics to reduce overcrowding.
More top news
A sea of tweed snaked its way through London today as the most dapper among us donned their finest and got on their bikes.
A protest is being held today against the closure of gay pub The Black Cap in Camden.
Four QPR hooligans caught on CCTV reeking havoc and attacking rival fans have been jailed.