Chiltern

Chiltern generally denotes the Chiltern Hills, a chalk upland area in Southeast England running northwest to southeast from the Thames Valley to the Chilterns escarpment. The hills lie mainly within Buckinghamshire and Oxfordshire, with parts in Hertfordshire and Bedfordshire, and are known for their rolling beech woodlands, steep escarpments, and numerous dry valleys. Large sections are designated as the Chilterns Area of Outstanding Natural Beauty (AONB), a status granted in 1965 to protect landscape, wildlife, and cultural heritage. The area contains diverse habitats, including ancient woodlands, chalk grasslands, and chalk streams.

Human settlement in the Chilterns has long been linked to routes through the ridge; towns and villages have developed along the crest and in valleys. The area is now a popular outdoor recreation destination and forms part of the London commuter belt, with walking, cycling, and historic sites drawing visitors.

In local government history, the name Chiltern referred to a non-metropolitan district in Buckinghamshire from 1974 until 2020; it was abolished under a structure of unitary Buckinghamshire Council, with the district's area incorporated into the new authority. The name remains in common use for the surrounding landscape and in various place names.

Outside the United Kingdom, Chiltern is also used in other places, such as Chiltern, Victoria, Australia, a rural town with historic heritage.