aerial photograph of Chatterley Whitfield Colliery,Chell Stoke-on-Trent Staffordshire UK. Chatterley Whitfield Colliery was once Staffordshires largest mine and the first million ton mine but now lies abandoned and in ruins. Coial has been mined at the site since the middle ages and by the Victorian period mining was being carried out on an industrial scale. The Biddulph Valley branch line was opened by the North Staffordshire Railway (NSR) in 1854 to bring the coal to market and the mine expanded with new shafts. In 1881 24 miners lost thier lives in a pit disaster at the mine following a fire and explosion. The mine prospered into the 20th century and in 1915 machinery replaced coal cutting by hand and by 1932 pit ponies had also been replaced by machinery. By the end of the 20th century increasing competition made coal mining at Chatterley Whitfield Colliery uneconomic and the mine closed in 1977. From 1977 to 1986 the site was used as a museum with underground trips, however the trips had to be stopped due to rising water levels and methane gas build ups. The museum closed in 1993 and since then the mine has been abandoned and lies derelict. The mine is slowly decaying and is now on Historic England's Heritage at Risk Register..