Platform 20 welcomed the first passenger train service in over six years, following a special agreement put in place between the South West Trains-Network Rail Alliance and the Department for Transport.
It means Platform 20 can be used to provide extra capacity at London Waterloo, the UK’s busiest station.
Preparations are continuing to bring Platform 20 fully into use for timetabled services from May 2014. It will help accommodate the 108 additional carriages which will be introduced from this winter to provide extra capacity for around 23,000 peak time passengers every day.
Six months ahead of its full opening, Platform 20 can be used when needed to relieve congestion at the station during times of disruption. Previously, there has been no spare capacity at Waterloo station.
Tim Shoveller, Managing Director of the South West Trains-Network Rail Alliance, said: “This is the first step in our plan to provide extra capacity to and from the UK’s busiest station by re-opening the former Waterloo International Terminal and delivering extra carriages on our busiest routes.
Further signalling problems caused delays to services between Havant in Hampshire and Chichester in West Sussex, between Shrewsbury and Wolverhampton and between Yeovil Junction and Salisbury in the West Country.
Another signalling problem, at Wandsworth Common in south-west London, led to delays to services through Balham station in south-east London, while illness to a passenger resulted in delays to services between Shenfield in Essex and London's Liverpool Street station.
No trains were able to run in and out of Moorgate station in London due to a lineside fire in north London. There were also delays in and out of another major London terminus - Waterloo - due to a signalling problem at Clapham Junction in south London.
All south West Trains services in and out of Waterloo are at a standstill after reports of a person on the track. Passengers have been told the emergency services have been called. The incident near Wimbledon began around twenty minutes ago.