This article originally appeared on PEDESTRIAN.TV and was scribed by travel-thirsty editor, Lucinda Price.

There’s something mystifying about things that are underground. There’s an element of danger to these places that make them so popular. Like, will the roof collapse? What happens if the lights go out? Who would be the first to get eaten if we’re stuck down here?!

Europe is full of these hidden hidey holes; particularly the Eastern region. One of the most famous is the Wieliczka Salt Mine in Poland, a 1,700-year-old underground city steeped in history and legend:

This 13th century monument is massive. It features 286km corridors, chapels, statues and even a got dang lake.

It originally opened up as a mine producing table salt way back in the day, and continued to do so up until as recently as 2007. In 1978, it was placed on the original UNESCO list of the World Heritage Sites.

https://twitter.com/slavicmyths/status/902727799777189888

Not only is it useful, it’s also beautiful. Huge chandeliers hand-crafted out of salt hang in the main quarters:

FLASHBACK: The incredible underground Wieliczka Salt Mine in Poland, with huge caverns dug out of the salt. pic.twitter.com/kraIp2GswT

— Time Travel Turtle (@michaelturtle) May 26, 2016

And visitors are even treated to hectic light shows featuring Chopin bangers:

Must-See Attraction When Travelling in #Krakow, #Poland: #Wieliczka Salt Mine Light Show With #Music by Frédéric #Chopin. #TravelTuesday #Travel pic.twitter.com/NOsEiGuj71

— Kristiina Vahvaselkä (@TravelWithXtina) November 21, 2017

You can see the enormity of this national treasure here, in this astonishing ant-hill-lookin’ map that shows it goes way down to 135M below ground:

Map of Wieliczka Salt Mine, Poland https://t.co/KFQvqsn0rE pic.twitter.com/NRxSshsA50

— mapmania (@_mapmania) November 23, 2017

The rock salt is naturally grey in various shades, resembling unpolished granite rather than the white or crystalline look that many visitors may expect. Pure magic.