Commuters using Holborn tube station are being warned to expect disruption until March 2018 while seven escalators undergo repair.
Work starts on 22 August, with two escalators out of service at a time, in order for the work to be finished as soon as possible.
The Piccadilly and Central lines will both continue to call at the station throughout the works, although there will be no access from the Central line to the Piccadilly line from 7.30am until 10am on weekday mornings until autumn 2017.
The station as a whole will be exit only from 7.30am until 10am on weekday mornings until the work is completed in March 2018.
Four of the escalators undergoing maintenance are between the ticket hall and the intermediate concourse for the Central line; the other three link the concourse and Piccadilly line platforms.
60,000 customers exit Holborn station every weekday, making it the 14th busiest tube station on the network during peak times.
The escalators at Holborn station hit the headlines recently after a 'stand on both sides' strategy was enforced: