-Harpur Hill

In 1940, Maintenance Unit No. 28 was the biggest chemical weapons reception and storage depot in the UK. Up to 46,000 individual chemical weapons were stored on the 500-acre site and surrounding country lanes. Wholesale burning of chemical weapons took place there after the war. In 1960 the site closed, and since then the underground tunnels there have been used to store cheese and alcohol and to grow mushrooms. There is also a toxic quarry lake where ordnance was also tested. Known to locals as “The Blue Lagoon,” it has a pH level of 11. Part of the site is occupied by the National Health and Safety Laboratory and the remainder is barren due to generations of misuse