An old disused Victorian cast iron warning sign attached to a long abandoned hoist at Cotehele Quay on the beautiful river Tamar Valley near Calstock, Cornwall, SW England, UK. Wording is WARNING - KEEP CLEAR OF THE HOIST THE LOAD AND CRANE HANDLES. a large section of the River Tamar Valley was bustling with copper, lead, silver, tin and arsenic mines. It is now part of a UNESCO World Heritage Mining landscape. It is a beautiful area mostly reclaimed by nature with the odd glimpse of its past. A fascinating area to explore.