5315 x 3543 px | 45 x 30 cm | 17,7 x 11,8 inches | 300dpi
Data acquisizione:
28 ottobre 2010
Ubicazione:
pakistan
Altre informazioni:
Salt has been mined at Khewra since 320 BC following discovery by Alexander's troops, in an underground area of about 110 square kilometres (42 sq mi). The main tunnel at ground level was developed by Dr. Warth in 1872 but has since been converted into a tourist resort. Khewra salt mine has estimated total of 220 million tonnes of rock salt deposits. The current production from the mine is 465, 000 tons salt per annum. The mine-head buildings have 19 stories, with 11 below ground. Only 50% salt is extracted and 50% is left as pillars to support the mountain. The salt-mine is 288 metres (945 ft) above sea level and extends around 730 metres (2, 400 ft) inside the mountains from the mine-mouth. The cumulative length of all tunnels is more than 40 kilometres (25 mi).
