Rail services across London will face major disruption over the bank holiday weekend as engineering work takes place.
Southeastern and Southern Railway say the work, carried out by Network Rail, is essential to “maintain and improve” rail infrastructure.
Services at Charing Cross, Waterloo East, London Bridge and Cannon Street will be affected.
On Saturday, no trains will run from Charing Cross or Waterloo East, with reduced services operating from London Bridge and Cannon Street.
Most routes will instead be diverted to run via London Victoria, which may increase pressure on alternative services.
Further disruption is expected on Sunday, with additional line closures and replacement bus services on routes serving southeast London and Kent.
Passengers are being urged to plan ahead and allow extra time, particularly when travelling through central London hubs.
On Saturday and Monday, several Southeastern routes will operate with altered timetables and diversions across London and the South East.
Services on the Paddock Wood line between London Charing Cross and Ramsgate or Dover Priory via Tonbridge will be diverted to run to and from London Victoria, with additional stops at Hildenborough.
Hastings line trains will run between London Bridge and Hastings, operating non-stop between London Bridge and Tonbridge via an alternative route, while services between Charing Cross and Tunbridge Wells will not run.
On the Maidstone East line, trains will start and terminate at London Victoria instead of Charing Cross, calling additionally at Bromley South.

Bexleyheath line services between London Victoria and Gravesend will run as normal, but routes from Cannon Street to Slade Green and from Charing Cross to Dartford via Bexleyheath will be suspended, reducing frequency to every 30 minutes.
Woolwich line trains between Cannon Street and Gravesend via Woolwich Arsenal will run to revised timetables and be diverted via Greenwich.
Meanwhile, Grove Park line services between Charing Cross and Sevenoaks will be rerouted to and from London Victoria, running non-stop between Victoria and Petts Wood.