Chiltern Hills
| Chiltern Hills | |
|---|---|
Near Nettlebed, Oxfordshire | |
| Highest point | |
| Peak | Haddington Hill |
| Elevation | 267 m (876 ft) |
| Dimensions | |
| Length | 74 km (46 mi) |
| Width | 18 km (11 mi) |
| Area | 1,700 km2 (660 mi2) |
| Geography | |
Location of the Chiltern Hills AONB in England | |
| Location | South East of England East of England |
| Country | United Kingdom |
| Counties | Bedfordshire Buckinghamshire Hertfordshire Oxfordshire |
| Range coordinates | 51°40′N 0°55′W / 51.667°N 0.917°W |
| Geology | |
| Rock type | chalk downland |
The Chiltern Hills or the Chilterns are a chalk escarpment in southern England to the northwest of London, covering 660 square miles (1700 sq km) across Oxfordshire, Buckinghamshire, Hertfordshire and Bedfordshire and stretching 45 miles (72 km) from Goring-on-Thames in the southwest to Hitchin in the northeast. The hills are 12 miles (19 km) at their widest.
In 1964, 833 square kilometres - almost half of the Chiltern Hills - were designated by the Countryside Commission as an Area of Outstanding Natural Beauty (AONB) under the powers established by the National Parks and Access to the Countryside Act 1949.
The northwest boundary of the Chilterns is clearly defined by the escarpment. The dip slope is by definition more gradual and merges with the landscape to the southeast. The southwest endpoint is the River Thames. The hills decline slowly in prominence in northeast Bedfordshire.