North Downs Way National Trail runs from Farnham to Canterbury and the White Cliffs of Dover, passing through two Areas of Outstanding Natural Beauty and the Kent Downs, including the Castle Hill section near Thurnham, Maidstone. The path was opened in 1978 and can be done in sections as it covers 153 miles of spectacular scenery, villages, historic sites including castles, cathedrals, and Kent countryside. The trail starts on the edge of the Surrey Hills, Farnham, Essex and covers a lot of areas in Kent, visit the main website for maps and information on attractions to visit on the trail. Also walks at https://www.surreyhills.org/discover/surrey-hills/leaflets/