Passengers are being advised about major changes to train services between Clapham Junction, Willesden, and Watford Junction from Saturday, 25 October.
Network Rail will carry out urgent work to renew a level crossing during a four-day closure over the October half-term school holidays.
The work is needed to keep the railway safe and reliable for passengers and freight services.
The essential improvements will secure the future of the infrastructure and allow continued access for vehicles to a busy industrial estate at Willesden.
Author's summary: Changes to train services in West London due to level crossing work.