Rail and Tube passengers endured morning rush-hour travel misery today, with services to a main London terminus badly disrupted.
Overhead wire problems in the Bethnal Green area of east London led to long delays and cancellations to trains in and out of London's Liverpool Street station.
Among those affected were air passengers using the Stansted Express to Stansted airport in Essex.
Two Underground lines were also hit by delays.
The Bethnal Green problems led to a reduced train service running between Shenfield in Essex and Stratford in east London to Liverpool Street
No trains were able to operate between Hackney Downs and Liverpool Street.
Trains between Cambridge and Liverpool Street were running only between Cambridge and Tottenham Hale, while the Stansted Express was reduced to a half-hourly service, starting and terminating at Stratford. Hertford East services were also starting and finishing at Stratford.
Delays to services that were able to run to Liverpool Street were as long as 60 minutes, with the National Express East Anglia train company advising passengers not to travel unless necessary.
Meanwhile, a signalling problem at Seaton Carew in Cleveland led to delays to services run by the Grand Central and Northern Rail train companies.
Buses replaced trains between Sunderland and Middlesbrough, with journey times extended by up to 30 minutes.
On the London Underground, late-running engineering work in the Harrow area of north west London led to severe delays on the Metropolitan line during the morning rush-hour.
There were also severe delays on the Piccadilly line, which was suspended between Rayners Lane and Uxbridge due to a signal failure in the Ealing Common area of west London. There were long delays between Acton Town and Rayners Lane.
Bob Crow, leader of the RMT transport union, said: "Tube delays are occurring on almost a daily basis, with worse to come over the winter because of the impact of maintenance cuts."
A Transport for London spokesman said: "Following late-finishing engineering work on the northbound Metropolitan line first thing this morning between Baker Street and Rickmansworth/Rayners Lane, services began operating at 5.57am.
"On the Piccadilly line, due to a signal failure, there was no service from 6am between Acton Town and Uxbridge. London Underground engineers worked hard to resolve the problem as quickly as possible and services resumed at 7.30am. We apologise to customers for disruption caused to their journeys this morning."