Albion fans gearing up to enjoy the FA Cup this weekend could have “longer” journeys because of planned engineering works.
Network Rail said it plans closures “years in advance” and apologised to people heading to the football or London Marathon.
Trains will be much busier than usual so passengers are being reminded to allow plenty of time for their journeys.
For Albion fans going to Wembley, Southern Rail recommends they travel to London Bridge for underground (Jubilee) services to Wembley or travel to London Victoria for underground services (Victoria and Jubilee) via Green Park to get to the game.
Lucy McAuliffe, Network Rail's Sussex route director, said: “We plan maintenance closures years in advance and we’re sorry that some passengers making their way to the football or to the marathon will have slightly longer journeys this weekend.
“Please be assured that the majority of routes into and out of London are running as normal.
“The railway needs regular maintenance to keep it running and the bumper package of essential repairs and improvements we have this week will keep passengers moving safely and reliably.”
All the travel information you need to know
Buses replace trains between Littlehampton and Brighton to allow for maintenance to track and switches and crossings, the moveable rails that allow trains to switch lines.
Some lines between Purley and Balcombe will be closed, meaning slightly longer journey times on the Brighton Main Line, as Network Rail’s tamping machines, which pack stone under the rails, will be operating.
On Saturday and Sunday, buses will replace trains between Streatham Hill and Crystal Palace / West Croydon as work to install a new signalling system continues in South London.
Also on Saturday and Sunday, no Thameslink trains will run between London Bridge and St Pancras International or Finsbury Park. Thameslink services from Brighton, Horsham and Rainham will run to amended timetables and terminate at London Bridge.
Services from Bedford and Luton will terminate at St Pancras; Thameslink services from Peterborough and Cambridge will be diverted to King’s Cross. Passengers can use Tube and bus services to cross central London.
Buses will also replace trains between Hastings and Ashford International, although services between Ore and London Victoria will still run. Network Rail will be replacing rails, sleepers and ballast near Winchelsea.
For more information, visit Southern Rail's website.
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