The work will affect trains on Sunday only (March 30).
Services will resume as normal on Saturday (March 29).
We have compiled all the details on these works so that you can plan your journey this weekend.
London Victoria services on Sunday:
Engineering work is taking place at London Victoria, closing all lines used by Southeastern at the station.
Trains between London Victoria and Ramsgate via Chatham will run to and from London Cannon Street instead and run non-stop between London Bridge and Swanley.
Trains between London Victoria and Dover Priory via Chatham will also be diverted to run to and from London Cannon Street and will run non-stop between London Bridge and Bromley South.
Trains between London Victoria and Ashford International via Maidstone East will run to and from London Cannon Street and run non-stop between London Bridge and St Mary Cray.
Trains between London Victoria and Orpington will run to and from London Blackfriars, calling additionally at Elephant & Castle.
Brixton station will be closed all day, you should use London Underground services for Brixton.
Trains between London Victoria and Dartford via Bexleyheath will not run.
Trains between London Cannon Street and Slade Green via Bexleyheath will run normally.
Passengers travelling between stations on the Bexleyheath Line and Dartford will need to change at Slade Green for a replacement bus because of further engineering work.
Sevenoaks:
Engineering work is taking place at Sevenoaks, closing some lines.
Network Rail is carrying out additional engineering work at Sevenoaks on Sunday morning to remove a speed restriction.
Stopping services between London Charing Cross and Sevenoaks via Grove Park will only be able to run between London Charing Cross and Orpington until approximately 9.05am.
This will affect trains in both directions.
The 6.50am, 7.31am, and 7.50am trains from Hastings to London Charing Cross train will be diverted via an alternative route and will be unable to stop at Orpington.
These two trains will only run between Hastings and Sevenoaks.
Trains from London Charing Cross towards Hastings will be able to stop at Orpington normally, but the 8.45am, 9.15am, and 9.45am trains from London Charing Cross to Hastings trains will start at London Bridge.
Dartford:
Engineering work is taking place at Dartford, closing all lines through the station.
Trains between London Cannon Street and Slade Green via Woolwich Arsenal will run normally.
Trains between London Victoria and Dartford will not run.
Trains between London Charing Cross and Gravesend will not run.
Services between London Charing Cross and Dartford via Sidcup will only run between London Charing Cross and Sidcup.
Replacement buses will run between Slade Green and Gravesend, and Sidcup and Dartford.