Kal Sardar Canyon in the eastern Iranian province of South Khorasan in the heart of desert is among the country’s astonishing natural tourist attractions and home to an exceptional phenomenon where one can experience a 10-degree difference in water temperature in the same river basin.
Some 25 kilometres off Tabas county in the heart of a desert in South Khorasan Province, eastern Iran, there is a river valley, flowing through Kal Sardar Canyon, which originates from a number of hot and cold water currents, the biggest one of which is called “Morteza Ali Bath”.
According to a Farsi report by the Mizan Online News Agency, the hot and cold waters, originating from these springs, join together in a river valley flowing through Kal Sardar Canyon, but do not completely mix with each other for some 300 meters due to their structural differences caused by the higher density of the hot water.
Being a unique phenomenon, the difference in the temperature of water in the river sometimes reaches 10 degrees. ‘Morteza Ali Bath’ and ‘Qanbar’ spring are the main sources of the hot and cold waters that flow to the river.
In the proximity of ‘Morteza Ali Spring [Bath]’ there is a historical site called Shah-Abbasi Arch which is said to be constructed in Safavid era (1501 to 1722).