EUREKA, Utah -- Underneath the mountains and deserts of the U.S. West lie hundreds of thousands of abandoned mines, an underground world holding serious danger and unexpected wonder. They are a legacy ...

Swaths of Pennsylvania and many other states are honeycombed with old, unstable mines that can cause the earth to suddenly give way and threaten people and property. That's what searchers in ...

This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated. Swaths of Pennsylvania and many other states ...