Chilmark is a Wiltshire village and civil parish of some 150 houses straddling the B3089 road, 11 miles (18 km) west of Salisbury, England.

The stream through the village, often dry in summer, flows some two miles (3 km) south to join the River Nadder.

About a mile south of the village, the stream passes (together with a minor road) through a ravine, as it descends into the Nadder valley.

In 1936 the quarries, and land extending further down the ravine, were bought by the Air Ministry and the site became RAF Chilmark, which was the home of No.

[5] Munitions were stored in the quarry caverns, and for a time the unit had extensive above-ground storage areas in woodland near Dinton and in Grovely Wood.

[10][11] Goods were transhipped under cover of a large shed, to/from a 2 ft gauge narrow-gauge railway which ran into the ravine and some of the former quarry caverns.

[18] A Planning Brief prepared by Salisbury District Council in 1999 concluded that options for re-use of the site, except for the former headquarters buildings, were limited owing to the presence of bat colonies and the possibility of contamination remaining from the storage of munitions.

[19] Until 2015, the former RAF headquarters and some 55 acres (0.22 km2) of land in and near the ravine were used by a private company as a training area for counter-terrorism security and explosives handling.

[21][22] During the night of 22 February 2017, officers from Wiltshire Police raided the bunker following information received that it had been converted for use as a cannabis farm.

Charges of conspiracy to hold persons in slavery or servitude were initially made, but dropped due to lack of evidence.

[23] It took ten days to search and clear the site, which was said to be the biggest cannabis factory found in the southwest region.