The UNESCO web-site entry says:
Much of the landscape of Cornwall and West Devon was transformed in the 18th and early 19th centuries as a result of the rapid growth of pioneering copper and tin mining. Its deep underground mines, engine houses, foundries, new towns, smallholdings, ports and harbours, and ancillary industries together reflect prolific innovation which, in the early 19th century, enabled the region to produce two thirds of the world's supply of copper.

The substantial remains are a testimony to the contribution Cornwall and West Devon made to the industrial revolution in the rest of Britain and to the fundamental influence the area had on the mining world at large. Cornish technology embodied in engines, engine houses and mining equipment were exported around the world. Cornwall and West Devon were the heartland from which mining technology rapidly spread. When Cornish and West Devon mining declined in the 1860s, large numbers of miners emigrated to work and live in mining communities based on Cornish traditions, in for instance South Africa, Australia, and Central and South America, where Cornish engine houses still survive.

The World Heritage site covers ten distinct locations from West Penwith to the Tamar Valley and into West Devon. The walker on the South West Coast Path may see the following coastal sites;

• St Just (West Penwith) including Wheal Edward, The Crowns, Botallack and Levant
• The port of Hayle
• Tregonning and Gwinear Mining area including Trewavas
• Camborne and Redruth Mining District including Portreath Harbour
• St Agnes area including Wheal Coates

More information about the area is available from web-site www.cornish-mining.org.uk