Mine changing room, Wieliczka Salt Mine. Here, the miners change their clothing and take showers. The clothing is stored on a hook raised up and down from ceiling to floor on a rope and pulley system. The salt mine at Wieliczka, Poland, is one of the oldest in the world. It was started in the 13th century and is still in use in the 21st century. By the 19th century, vast underground caverns had been excavated to depths of several hundred metres, including statues sculpted out of the salt deposits. In 1978, the mine became a UNESCO World Heritage Site.