World's top underground tourist attractions

By Tamara Hinson, for CNNUpdated 18th November 2013
Well seasoned ... a Wieliczka mine chamber.
Well seasoned ... a Wieliczka mine chamber.
wieliczka salt mine
Pre-plague, Edinburgh's busiest street.
Pre-plague, Edinburgh's busiest street.
VisitScotland.
"Shanghai" not as in place but "sailor-snatching."
"Shanghai" not as in place but "sailor-snatching."
Portlandwalkingtours.com
Al Capone knew a nice smuggling route when he saw one.
Al Capone knew a nice smuggling route when he saw one.
Chicago Connection Tour