the valley of levers water beck below brim fell holds part of the coniston coppermines, a huge complex of shafts and tunnels extending over a square mile. the mine was at its most productive in the 1850s, declining in output until closure in 1915. since then there have been occasional attempts at reopening, principally in 1954, but tourism has gradually taken over as the main activity in the valley. the mines exploited a number of veins, the copper-bearing mineral chalcopyrite being the main ore, although some nickel, cobalt and lead were also extracted. the paddy end section of the mine on the lower slopes of brim fell was the most productive, with levels passing beneath the bed of levers water. simons nick, a large (and dangerous) multi-shaft opening above the dam is the most obvious remaining feature.