London Midland has announced closures of the Abbey Line next month.
The line that runs from Watford Junction to St Albans Abbey will be shut the weekend of Saturday, August 9, as part of the improvement works in the Watford area.
The services will re-open on Tuesday, August 26.
During the closure, an hourly bus service will run between Watford Junction and St Albans City train stations in both directions, calling at Watford North, Garston, Bricket Wood, How Wood, Park Street and St Albans Abbey.
London Midland has advised customers plan and check their journey at nationalrail.co.uk.