Chislehurst Caves

Chislehurst Caves is a 22 miles (35 km) long series of intersecting tunnels in Chislehurst, Bromley, in Southeast London, England. They were used for chalk mining and flint mining from the 13–19th centuries..

Today the caves are a tourist attraction and although they are called caves, they are entirely man-made and were dug and used as chalk and flint mines. The earliest mention of the mines is around 1250 and they are believed to have been last worked in the 1830s.

During the early 1900s, the caves became a popular tourist attraction. In World War I they were used as an ammunition depot associated with the Royal Arsenal at Woolwich. They were used for mushroom cultivation in the 1930s.

During World War II, when the aerial bombardment of London began in September 1940, the caves were used as an air raid shelter. Soon they became an underground city of some 15,000 inhabitants with electric lighting, a chapel and a hospital. Shortly after VE Day the shelter was officially closed. One baby, christened Rose Cavena Wakeman, was born in the caves.

In 1903, William Nichols, then Vice President of the British Archaeological Association, produced a theory that the mines were made by the Druids, Romans and Saxons. This theory was used to give names to the three parts of the caves. Tour guides point out supposed Druid altars and Roman features. However this is at best speculation as the earliest documented evidence for a chalk cave is in 1737. An opposing article in the next issue showed the similarity of the workings to coal mines in the Newcastle area, and argued that most of the excavation had been made in the last two centuries and that the evidence for any dene-holes was slight. The caves were used between 1830 and the 1860s for producing lime. The 25 inch to a mile (approx 1:2,500) Ordnance Survey map of 1862–63 describes the place as a "chalk pit" and marks an "engine house" and two remaining kilns. A further investigation produced, among other evidence, a letter from the son of one of the workers.

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