Obsidian Urbex: underground cavern

The network explored is identified locally as Grange Cavern, which was converted into an underground military museum in the 1970s and is reported to have occupied roughly 3,250 m² of exhibition floor space (gronkue.com). The museum closed to the public around 1989, and several contemporary reports and urbex write-ups say much of the collection was dispersed or loaned out and never fully accounted for afterward (28dayslater.co.uk). During World War II the caverns were used as an RAF bomb store and secure Ministry of Supply depot, a wartime function documented in Subterranea Britannica’s site file for Grange Caverns (subbrit.org.uk). The photographer behind Obsidian Urbex publishes under the name Janine Pendleton on Patreon and operates a portfolio site that emphasizes photography-led documentation rather than revealing precise site coordinates (patreon.com). Multiple recent urbex teams have uploaded explorations of the same underground military complex, including videos by Zed Urbex and Underground Explorer that show interior vehicle bays and long echoing passages in footage from the past year (youtube.com). Visitors and reports note persistent on-site hazards: high subterranean humidity that damaged metal exhibits, pools of toxic‑turquoise water from chemical leaching, and accounts of a landowner who patrols the surface with an aggressive dog near access points (youtube.com). Heritage researchers list the location as now empty of its former displays, with Subterranea Britannica’s entry updated in February 2026 describing the WWII store and subsequent museum closure before its current derelict state (subbrit.org.uk).