The Lake District mountains are full of mineral veins. Many have been discovered and worked over the past 1,000 years. Many still remain to be discovered. The last working metal-ore mine in the Lake District, the Force Crag Mine, closed in 1986. It is believed that mining commenced at Force Crag during the fifteenth century. Today, remains of this past extensive industry lie abandoned on the mountainsides and are now considered to be an iconic reflection of the Lake District's industrial past. They blend in well with other iconic 'industrial' structures such as stone walls, drove roads and fell farms that exist throughout the district. For many years now industrial historians have studied these workings and also the lives of the skilled miners who spent their careers high on Lake District mountainsides, working the veins. Concern for the loss of many of these ancient sites has developed over recent years. In 1989 a report produced by local industrial archaeologists highlighted a list of twenty-seven former mining sites on the fells considered to be of such exceptional importance to the history of the Lake District communities that they should be given future protection. Many of these sites have been included in this definitive illustrated guide.