
Salt mines are special compared to other underground excavation sites: once they are closed for extraction purposes, they can be opened for visitors, or for storage purposes—all because of their unique microclimate with natural air-conditioning and constant temperature and atmospheric pressure all year.
Our collection has two main goals: to show how beautiful these artificial caves and huge underground chambers once were, and to show some of the most interesting ways these depleted salt mines are being used. Let us know in the comments if you've ever explored one.
Circa 1900: Avery Island Salt Works, Akzo Salt Incorporated, Avery Island, Iberia Parish, LA.

Source: Library Of Congress
Interior of a salt mine, circa 1920.

Source: Detroit Publishing Company/Library Of Congress
Inside the salt mines of Aknaszlatina, Hungary (now: Solotvyno, Ukraine), circa 1940.

Source: Arcanum

Source: Arcanum

Source: Arcanum

Source: Arcanum

Source: Arcanum

Source: Arcanum

Source: Arcanum
Inside the Royal Hungarian Salt Mine of Désakna (now: Ocna Dejului, Romania), circa 1940.

Source: Arcanum

Source: Arcanum

Source: Arcanum

Source: Arcanum

Source: Arcanum
Salt mine of Aknasugatag, Hungary (now: Ocna Șugatag, Romania), circa 1940.

Source: Arcanum
Amazing patterns of rock in the mine of Marosújvár, Hungary (now: Ocna Mureș, Romania), circa 1940.

Source: Arcanum
This is how the main chambers look nowadays inside the salt mine of Slănic, Prahova, Romania.

Source: Andrei Stroe/Wikimedia Commons

Source: Beradrian/Wikimedia Commons
The salt mine in Nemocon, Colombia was converted into a museum and tourist attraction.

Source: Pedro Szekely/Wikimedia Commons
The Praid mine was a large salt mine in central Romania, close to Praid (once Parajd, Hungary), now known for its healing effect on respiratory and allergic illnesses.

Source: Octav Druta/Wikimedia Commons
Salina Turda, the salt mine of Turda, Romania (once Torda, Hungary) has been a therapy center and tourist attraction since 1992. It's considered as one of the most beautiful underground places in the world.

Source: Cristian Bortes

Source: Cristian Bortes
Saint Kinga Cathedral at the The Wieliczka Salt Mine, Poland, is alsoa major tourist attraction.

Source: Brian Snelson
The underground vaults of the Law Library Microform Consortium, where LLMC preserves all its hard copy material 650 feet underground in an old salt mine storage facility in Hutchinson, Kansas.

Photo: Richard C. Amelung/Saint Louis University/AP
Pakistani visitors inside the centuries-old Khewra salt mine, located 160 kilometers south of Islamabad. The mine offers experimental allergy-related asthma therapy.

Photo: B.K. Bangash/AP
Storage chamber for low- and medium-grade radioactive waste produced by medicine and nuclear power plants, in the former salt mine called Schacht Asse II, in Remlingen, Germany.

Photo: Joerg Sarbach/AP
A concert hall installed in the salt mine chamber N41 at a depth of 984 feet below Soledar, Ukraine.

Photo: Photomig/AP
Visitors inside the Zipaquira Salt Cathedral, built into the walls of a salt mine nearly 600 feet into a mountain of Zipaquira, Colombia.

Photo: Javier Galeano/AP
DISCUSSION
These are a few pictures from my trip to Wieliczka.
Underground "river" with Tunnel of Love style ride. It was shut down after some military personnel got carried away and tipped the boat. They were all stuck under the boat and drowned because the water's salinity caused them to be hyper buoyant.
Close up of the chandeliers in the cathedral, made of pure salt.
A statue carved of pure salt, it is a likeness of King Casimir III the Great one of Poland's most beloved kings.
And just a picture of some artwork carved into the salt walls of the cathedral.
It really was a great trip, I highly recommend that if you find yourself with a spare afternoon in Krakow go ahead and hop on a bus and take the tour, its really something.