Days after Albert died, in 1861, Victoria ordered that the mausoleum, above, be built in the grounds of the Windsor Castle retreat of Frogmore House. Decorated with frescoes, plaster angels and marble, it took ten years to complete. When Victoria died, 40 years after her husband, her remains were placed there with his.

English Heritage is so concerned about the Royal Mausoleum that it listed the structure as at risk of being lost to the nation. Restoration is expected to cost £2 million.

English Heritage said: “The building suffers from condensation and damp. Parts of plaster angels are falling from the ceiling and frescoes are in need of repair. The downpipes are not able to cope with heavy rainfall.”

The mausoleum is open to the public three days a year. Funding is covered by the Government’s £15 million annual grant for the upkeep of royal palaces, which Buckingham Palace says needs to be increased.