The repairs began last month, and will continue to affect trains on Saturday and Sunday (June 14 and June 15).
We have broken down the details so you can plan ahead this weekend.
All weekend:
Engineering work on the Blackheath Tunnel will continue to take place this weekend, closing all lines between Blackheath and Charlton.
No trains will run between Blackheath and Charlton.
Most trains between Dartford and London Cannon Street via Woolwich Arsenal or Lewisham will be diverted to run via Greenwich, however at peak times some of these trains will be diverted to run via Bexleyheath.
There will be two trains per hour between Blackheath and London Cannon Street.
At peak times some additional trains will run between Dartford and London Cannon Street via Bexleyheath. Alternative travel options:
Passengers can use the following routes at no extra cost:
London Bus routes 54 and 380 between Blackheath, Charlton and Woolwich, and between Charlton and Greenwich.
Docklands Light Railway between Lewisham and Greenwich.
Passengers can also travel with your ticket at no extra cost between London Bridge and Dartford to make connections on the Woolwich and Bexleyheath lines, or towards Petts Wood, though a break of journey will not be possible at these points.
