Millions of rail passengers suffered miserable journeys this morning after a series of problems led to long delays on major routes.
The difficulties included hold-ups in and out of Victoria, King's Cross, Moorgate and Fenchurch Street stations in London.
There were also long delays affecting services run by five train companies after a body was discovered on the line south of York.
The problems at Victoria came after smoke was seen pouring from the engine of an empty Gatwick Express train at the busy London terminus.
The station was evacuated and, although it later reopened, long delays persisted through the morning, with some London-bound rush-hour travellers held up outside Victoria for up to an hour.
There were also delays of up to 90 minutes to services in and out of Fenchurch Street due to a broken-down train in the Limehouse area of east London.
A train failure was also the cause of disruption at New Southgate in north London and this led to delays to services between Stevenage in Hertfordshire and King's Cross and Moorgate stations.
The problem near York, at Colton Junction south of the city, caused delays of up to 80 minutes - hold-ups which were expected to last until at least 1pm. Passengers on the London to Scotland East Coast line were among those affected.
In the West Midlands, a signalling problem at Wolverton was causing delays between Rugby/Northampton and Milton Keynes Central, while a broken-down train at Chelmsford in Essex led to delays of up to 60 minutes between Colchester and Shenfield.
Another broken-down train - this time at Angmering in West Sussex - meant buses had to replace trains between the coastal resorts of Worthing and Littlehampton.
Nearby, a signalling problem at Chichester led to delays between Barnham and Havant in Hampshire.
In East Anglia, an electrical supply problem at Cambridge meant buses had to replace trains between Cambridge and Ely.