Ham Common is an area of common land in Ham, London. It is a conservation area in and managed by the London Borough of Richmond upon Thames. It comprises 48.69 hectares (120.3 acres), the second largest area of common land in the borough, 2 acres (0.81 ha) smaller than Barnes Common. It is divided into two distinct habitats, grassland and woodland, separated by the A307, Upper Ham Road. It is an area of ecological, historical and recreational interest, designated a Local Nature Reserve.
More information on the Wikipedia page [1], and the Richmond Council page is [2].