The Wandle Valley Regional Park is a legacy of the Industrial Revolution. Its fast-flowing waters powered about 100 mills from Croydon and Carshalton to the Thames at Wandsworth. The high level of industry prevented the builders of London’s sprawling suburbs from building too close to the river. With the remaining riverside estates of local entrepreneurs, this left a string of attractive parks linked by wilderness and the Wandle Trail. That legacy brings together some 900 hectares of south London’s open spaces under a unified vision.