GLA 40: Chislehurst Caves, Potential RIGS

GLA 40: Chislehurst Caves, Potential RIGS
London Borough of Bromley, TQ 431 696
Ownership: Private. Regular paid tours are available.

A man made subterranean chalk mine dating from mediaeval times but mostly exploited during the 1800’s. Mining chalk from a drift mine entrance at the bottom of a valley using a pillar and stall technique has been carried out for over 100 years until the mines closed in 1866. The site is famous for its use as an air-raid shelter in World war two. The site is privately owned and has regular guided tours.

The Geology

The caves provide a rare opportunity to view unweathered Chalk in the Greater London Area. Geologically one of the main points of interest is the well exposed junction between the eroded top of the Upper Chalk and the Thanet Sand. It is one of the rare good exposures of the Bullhead Bed. With a full exposure of the top of the chalk there is a potential for more research on the detailed age at the top of the section. Elsewhere under London it is usually dated as Seaford Chalk Formation but there is a possibility that the age might be slightly younger at Chislehurst and go into the base of the Newhaven Chalk Formation. Details of research are described in GA Guide 68, pp 105-111


This site is open to the public Wednesday to Sunday (every day during local school holidays) with 45-minute tours from 10am with last tour at 4pm. The nearest station is Chislehurst. Further information is on or 020 8467 3264.

Exposed sediments at Chislehurst Caves
Source: London’s foundations, page 191 (Vernon Marks)


Site Map OS Topography © Crown Copyright
Source: London’s foundations, page 186

gla40 map

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