Yet the Wieliczka Salt Mine in southern Poland was declared a UNESCO World Heritage Site in 1978 and proclaimed by Poland as a national monument in 1994.
A salt mine?
So why would a salt mine end up on the list of World Heritage sites?
The Wieliczka Salt Mine?Four hundred and forty-three feet beneath the City of Wieliczka (population 20,000, in the metropolitan area of Karków, Poland), the Wieliczka Salt Mine has continuously extracted table salt from the time it was constructed in the 12th century by a local duke. The salt mine was first mentioned in 1044 and didn't cease operations until 1992 (some sources say 1996 and 2007), due to heaving flooding. Regardless, it's one of the oldest and longest operating salt mines in existence and still produces brine.
From the outside, the mine appears exceptionally well kept but ordinary, and on the interior, you will find the expected look and equipment of a salt mine.