"The famous salt mine" a Wieliczka Travel Page by Robert_Hun

The mine has been working for 900 years now. It used to be one of the world's biggest and most profitable industrial establishments when common salt was an equivalent of today's oil.
There are labyrinthine passages, giant caverns, underground lakes and chapels with sculptures made of crystalline salt and rich ornamentation carved in salt rock.
It has about 200 kilometers of passages and more than 2,000 caverns. The tourist route starts at 64 meters depth and ends at 135 m. Still below, some 210 m deep, there is a sanatorium for those suffering from asthma and allergy.
As the mine has a unique acoustics, occasionally concerts and other events take place in the biggest chambers.
It's a UNESCO World Heritage site.

Wieliczka is just south-east of Krakow (15 minutes by car), accessible by train and bus, too.
Ticket for foreign visitors (incl. a compulsory group tour guide in English) costs 55 PLN (16-17 USD), you get 20% discount between November and February. Car parking 7 PLN, use of camera 10 PLN.
Open:
April-October: 07.30-19.30
November-March: 08.00-17.00
Be prepared for long queue (maybe even 2-3 hours) in high season and week-ends.
You will use the staircase down but a lift back to the top and this (i.e. to exit) can take long waiting time as well.
The tour takes cca. 2 hours but if you want to see the mine's museum, you have to count double duration.
More info...