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.
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