Euston Station will be closed for the next three weekends – including Bank Holiday Monday – while engineers work on a major rail route.
The busy station will be shut on August 18 and 19, August 25 to 27 and September 1 and 2.
West Coast main line passengers are being urged not to travel on these dates as engineers replace the north Wembley junction, one of the major intersections on Europe’s mixed-use railway.
No trains will run on the West Coast main line, including services to Birmingham, Manchester and Glasgow.
Virgin trains will be running services north from Milton Keynes Central on these dates, but there will be no southbound service from the Buckinghamshire station.
Rail operators said the three-week summer period was considered the least disruptive for the work to be carried out.
Shops in the station and access to the London Underground will remain available during the closure.
If customers have to travel, they are advised to expect busier trains and longer, diverted routes.
Martin Frobisher, route managing director for Network Rail’s London North Western route, said: “There is never an ideal time to shut the railway but these three weekends are the least disruptive times to do it.
“We have worked together for the past three years with train operators to carefully plan this closure of the railway in a way that minimises impact on customers.
“It’s vital the track at north Wembley is replaced to continue to safely meet the huge demand of passenger and freight rail services on the West Coast main line. This work will result in better, more reliable journeys in future.”
Andrew Conroy, customer experience director for London Northwestern Railway said: “Our aim is to keep people moving if they have to travel on these dates. Improvement works are never convenient for anyone, but we have a tried and tested plan for operating buses to connect with alternative routes to and from London when Euston is closed.
“We still advise customers to travel on alternative days as these options will take significantly longer.”