Morden Hall Park is 125 acres of meadow, woodland and water at the southern end of the Northern line, left to the National Trust in 1941 by Gilliat Hatfeild on condition that the public could always walk it for free. The Hatfeild money came from snuff, and the mills that ground tobacco still stand beside the River Wandle, which splits into channels and mill races crossed by a web of little footbridges. The Edwardian rose garden holds more than 2,000 roses, and the wetland boardwalk threads through reed beds where herons, little egrets and kingfishers are regular sightings. There is an adventure play area, a large garden centre, two cafes and a second-hand bookshop that reviewers rank among the best they have found. Dogs are welcome, on a lead in the rose garden, on the boardwalk and around the buildings. Tips from regulars: the cafes and bookshop keep shorter hours than the park, so plan food around them and remember the loos in the family hub.