These psychedelic photographs give a rare glimpse inside the walls of an abandoned salt mine in Russia.
After years of mining deep into the Earth's crust, layers of a carnallite now line the tunnels with a spectacular mix of coloured rock.
Used in the process of plant fertilisation, the mineral can appear in a variety of colours including white, red, yellow and blue.
Although a small part of the mine is still in use, miles of tunnels now lay abandoned an are only accessible with a special government permit.
But that didn't stop photographer, Mikhail Mishainik, 29, from exploring the network of passageways in the industrial city of Yekaterinburg, Russia.
The Russian adventurer and his barmy bunch of explorers spent over 20 hours exploring the dimly-lit labyrinth and have even stayed overnight on at least three occasions.
But if sleeping 200 metres below the Earth's surface isn't nerve wracking enough, the gang are also at risk of gas leaks and landslides.
Mikhail told Caters News: "The mines are huge and stretch many kilometres in width and length, a single tunnel can be over four miles long.
"The air is filled with small particles of salt and if we didn't have our torches switched on it would be pitch black.
"It is easy to get lost as many of the passageways look the same, we navigate our way around very carefully.
"Many people know about the mines but it is very difficult to access them if you don't have an official permit.
"We take our safety very seriously but of course there are always dangers.
"There is the possibility of a gas leak from chemicals such as methane, hydrogen sulphide carbon dioxide as well the risk of a landslide.
"The danger element is part of the fun and its a special feeling being somewhere very people have seen."
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