Chiltern

Etymology
en, but thought to derive from a toponym, presumably related to height. The other placenames derive from the English hills.

Proper noun

 * 1) * 1771, Encyclopaedia Britannica, 1st ed., Vol. II, p. 184:
 * CHILTERN, a chain of chalky hills, running from eaſt to weſt through Buckinghamſhire.
 * , abolished on 31 March 2020.
 * , abolished on 31 March 2020.
 * , abolished on 31 March 2020.