Annual checks are carried out on the towers, which were built between 1722 and 1745 by Nicholas Hawksmoor and John James, and constructed from Portland stone to an early example of a Gothic revival design.
While assessing the building’s stone, Lewis and Adam had a panoramic view of London. Many spires and arches had to be navigated as they scaled the Gothic Revival church, before skilfully winching themselves down.
Westminster Abbey has been the location of the coronations of 40 English and British monarchs, most recently of King Charles III in May this year.
The most recent cleaning and restoration work was carried out in 1993, when the late Duke of Edinburgh unveiled an inscription at the base of the north-west tower.
Westminster Abbey Foundation said it cost more than £14m a year to maintain the abbey.
“In common with homeowners across London, Westminster Abbey has to care for its building, and has an ongoing programme of review and maintenance,” a spokesperson said.
“This work includes an annual survey of the West Towers by specialist abseilers with a knowledge of historic buildings who skilfully analyse their condition at heights of over 200ft (61m) to identify any remedial work which may need to be undertaken.”