The walks in this guide are all within the circumference of the M25 motorway. Many people, including Londoners themselves, may be surprised by how much open, attractive and unspoilt countryside still survives in an area that is often thought to comprise little more than sprawling suburbs and congested roads. Routes make use of London's famous parks - Hyde, Battersea, Regent's and Greenwich; go along the Thames and the Grand Union Canal; visit open spaces such as Ashstead and Wimbledon Commons, and Hampstead Heath; explore the ancient woodlands of Epping Forest and Enfield Chase; and on the outskirts of Greater London the North Downs in Kent and Surrey.