The team behind the bid wants to preserve 10 mining areas

The go-ahead by Unesco gives the area the same status as the Great Wall of China and the Taj Mahal.

In the 18th and 19th Centuries the mines of the area were the world's largest source of tin and copper.

The decision was taken by Unesco's World Heritage Committee meeting in Vilnius, Lithuania.

For a time the region was the world's greatest producer of tin and copper Nick Johnson, bid manager

It follows a submission by the Secretary of State for Culture, Media and Sport on behalf of the World Heritage team.

The team behind the bid wants to preserve 10 mining areas from St Just in the west to the Tamar valley.

World Heritage Site bid manager Nick Johnson said the cultural identity of Cornwall and west Devon was "transformed by mining during the 18th and 19th centuries".

"For a time the region was the world's greatest producer of tin and copper and the area provided the essential raw materials for the industrialisation of the world.

"This took on global significance as a result of the mass migration of miners overseas," he said.

He said 175 locations worldwide had known Cornish mining connections, and an estimated 6m people worldwide were descended from migrant Cornish.

It has been estimated that the new status will bring in an extra 60,000 visitors to Cornwall and west Devon every year.

World class

The World Heritage Convention, adopted by Unesco in 1972, provides for the identification, protection and conservation of natural and cultural sites of outstanding universal value.

More than 800 such sites can be found across the world, including 628 cultural, 160 natural and 24 mixed properties in 137 countries.

Cultural examples on the list also include the Tower of London.

The Cornwall and west Devon world heritage site bid was submitted for nomination by the government in January 2005.

Culture secretary Tessa Jowell said: "I am delighted that the World Heritage Committee has recognised the outstanding universal value of the Cornwall and west Devon Mining Landscape and its important contribution to national and international industrialisation.

"This historic area and its people have significantly influenced the development of mining and engineering culture, not just in the UK, but across the rest of the world."