Sunday, December 6, 2009
Underground Kish Kariz
The Kish ghanat in Kariz, Iran is more than 2,500 years old and currently has been converted into an underground town at a depth of 16 meters below the surface, with an area of more than 10,000 square meters. Its ceilings are eight metres high and mostly covered by fossils, shells, and corals estimated to be 270 to 570 million years old. Its experienced advocates took on the painstaking design work and have tried to keep its historic fabric while providing new uses during its renovation. In its first phase, Kariz underground city will be functional with its handicrafts stands from Iran and the world, traditional and modern restaurants, amphitheatre, conference hall, and art galleries.
The ghanat is an ancient system found in arid regions that brings groundwater from the mountains, following a water-bearing formation (aquifer), and emerge at an oasis, through a series of tunnels. The tunnels perhaps several kilometers long, are roughly horizontal, with a slope. This allows water to drain out to the surface by gravity to lower and flatter agricultural land. Considered to be the oldest feat of human engineering, this system can be found still working in Iran.
People who were living on Kish Island centuries ago, with their inherent Iranian intelligence and talent in building aqueducts, dug the coralline layers of Kish Island in search of potable water, and were rewarded with fresh water. For centuries afterwards, the sweet water of Kish Island not only relieved the thirst of local residents, but was also exported to neighboring states and swapped with sugar or cash.
Kariz is situated in the heart of the only coral island in the world. The earth excavated from Kariz has much medicinal value and will have abundant use in "mud treatment". Kariz was built by the inhabitants of Harireh city. The ancient water management system collected water from 274 wells in an area of 14km² and conducts the water to a central filter shaft. The central shaft is filled with three layers of filter material. The top layer was coral gravel which was used to neutralize the acids in the water and filter bigger solids in the water. Then a layer of coral grit with clay was filtering fine solids, and the lowest lever was made of marn, a special sort of clay.
During the past years, three kilometers of tunnels with a total area of 14,500 square meters have been dug at a depth of 14 m underground beneath a 7-meter layer of coral without using modern tools and solely by using a simple ax and human hand. Temperature inside the tunnels of the underground city is fixed at 22-25 degrees centigrade and has added to the attraction of the complex for visitors, especially in hot season.
The main center of Kariz, which is intersection of three aqueducts and has an area of 10,000 square meters, is located at Olympics Square of Kish Island and is used to introduce Iranian and foreign visitors to aqueduct as a valuable cultural heritage of Iran.