Century House, London

Century House is a 22-storey building located at 100 Westminster Bridge Road in London. The building was designed in the modern style and constructed between 1959 and 1964. It became the home of the Secret Intelligence Service following their move from 54 Broadway in 1964. Though the location of their Broadway headquarters was classified information, The Daily Telegraph reported that it was "London's worst-kept secret, known only to every taxi driver, tourist guide and KGB agent".
After 21 years in service as the headquarters of SIS, Century House was described as "irredeemably insecure" in a 1985 National Audit Office report with several security concerns raised. Chief among those concerns was that the building was made largely of glass, and had a petrol station at its base. The SIS subsequently moved its headquarters to a new building at Vauxhall Cross in 1994, after which Century House was acquired by a developer, renamed the Perspective Building, and converted into an apartment block to a design by Assael Architecture. The conversion work was completed in 2003.