Hampstead Heath

Hampstead Heath (locally known as "the Heath") is a large, ancient London park, covering 320 hectares (790 acres). This grassy public space sits astride a sandy ridge, one of the highest points in London, running from Hampstead to Highgate, which rests on a band of London Clay. The Heath is rambling and hilly, embracing ponds, recent and ancient woodlands, a lido, playgrounds, and a training track, and it adjoins the stately home of Kenwood House and its grounds.
www.cityoflondon.gov.uk/Corporation/LGNL_Services/Environment_and_planning/Parks_and_open_spaces/Hampstead_Heath