Rail passengers faced travel misery on Tuesday as services to and from three key stations - Euston, Paddington, and Marylebone - were simultaneously hit by major disruption.
Major disruption hit services between Watford Junction and Euston with trains cancelled or delayed by up to an hour until mid-afternoon.
A signalling fault earlier caused major disruption to trains to and from Marylebone for hours, but this cleared around 3pm.
The issue on Tuesday morning left frustrated passengers stuck for more than an hour on stationary trains, and people told not to travel on the Chiltern Railways network
Major disruption also earlier affected Heathrow Express, Elizabeth Line, and Great Western Railway services between Paddington and Slough/Heathrow Terminals. Lines have also reopened there, and disruption was understood to have ended around 1pm.
But misery continued for commuters as an electricity failure hit London St Pancras International. It will mean delays to Southeastern services to and from the station until 7pm, National Rail said.