This National Trust property is on the Herts and Bucks border, between Aylesbury and Hemel Hempstead. It covers a large area of woodland and chalk downland at the north end of the Chiltern Hills. Visitor attractions include:
- the towering Duke of Bridgewater Monument, built in 1832, which provides great panoramas
- Ashridge park and woods; excellent for walking, cycling, horse-riding and kite flying
- Pitstone Hill and Windmill; one of England's oldest surviving post-mills (an early form of windmill) which dates from 1627 and is open to the public on summer Sunday afternoons.
- a visitor centre, shop and café
Admission is free but donations are welcome.