From the surface there is nothing special about the hilly countryside around the city of Cankiri in Turkey.
However 1,300ft below ground is a stunning salt mine which was first dug by primitive humans around 5,000 years ago.
Despite its incredible age the mine is still in use today and produces more then 500 tonnes of salt each year which is used in cooking and for a range of souvenirs.
This is the salt mine outside of Cankiri in Turkey which began being mined in 300BC and is still in use today
The original miners were Hittites, an ancient race of people who had an empire in the Middle East and used primitive tools and their hands to extract the salt
The pictures were taken by Melih Sular, 32, as part of the 2013 National geographic photography cometition
According to a 1971-79 survey there is still more than 1billion tonnes of ore left in the mine, which is extracted using machines and underground blasting.
These pictures were taken by Melih Sular, 32, who was guided through the caves by Murat Danaci as part of the National Geographic photography contest.
He said: 'When I first entered the salt cave I was afraid. I thought to myself: "What happens if it collapses?"
The mine produces about 500 tonnes of salt every day which is sold on for use in cooking and as souvenirs
While temperatures on the surface regularly reach 91F (33C) they rarely stray above 59F (15C) in the caves
At its deepest point the mine extends down more than 1,300ft (400m) below the ground
'The cave is cool and scentless, which is because it is a very old salt cave. The walls are all made of rock salt and the texture is varied because of the digging machines used.'
The ore extracted from the mine often comes in at 90 per cent purity
He added: 'I've never seen anything like it before. The most striking part of the caves is the old gallery, which were dug by Hittites.
'It's interesting because they dug this gallery with simple tools and their own hands, unlike today's methods.'
While temperatures in the city regularly reach 92 Fahrenheit (33C), the mercury never strays much above 59 degrees (15C) inside the ancient caves.
The Hitties were an ancient race who built an empire in the Middle East which covered most of modern-day central Turkey, northern Syria and Iraq and flourished between 1,400 and 1,200BC.
They were famous for their skill in building and making chariots and wrote in a hieroglyphic-type language called cuneiform.
They were eventually destroyed after several costly wars, particularly a defeat to the army of Ramses II, pharaoh of the Egyptians. Competition for succession of the throne also drained their resources.
Today the mine has 16 workers and contains a small canteen, a mosque, repair room, workshop and a first aid room.
All the ore extracted from the mine, which measures in at around 90 per cent purity, is taken by diggers to nearby railway tracks where it is transported to a factory for processing.
There is so much salt contained in the ground around the mine that it appears around the edge of a nearby lake after being dissolved into the water.
The Hittites who first mined here in 3000BC, had an empire which reached from Turkey into Syria and Iraq
The 16-strong workforce use digging machines and dynamite blasts to extract the salt from the clay soil
Read more: http://www.dailymail.co.uk/news/article-2508731/Salt-earth-The-5-000-year-old-mines-inside-caves-tunnels-Turkey-use-today.html#ixzz2l8Y4FRZI
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