Sandwiched between Hyde Park and St James's Park, Green Park is a quieter, more peaceful space than its neighbours. There are no lakes, no buildings - just 19 hectares of mature trees and grassland.
The site is said to have originally been a burial ground for lepers, and its quiet green spaces were once a notorious duelling ground, as well as a popular stomping ground for highwaymen and thieves.
The park now conceals underground Government offices and corridors, linking the nearby Royal palaces, running beneath the east side of the park. The rooms are thought to be conversions of some of the tunnels built as part of the Cabinet War Rooms from the Second World War.