Since its foundation in 1518, the RCP has had five headquarters in London. The current Grade I listed building in Regent’s Park was designed by architect Sir Denys Lasdun and opened in 1964. Considered a modernist masterpiece, it is one of London’s most important post-war buildings. The current Grade I listed building in Regent’s Park was designed by architect Sir Denys Lasdun and opened in 1964. Considered a modernist masterpiece, it is one of London’s most important post-war buildings.