After hearing the word cave most of us remember Ali-Sadr, the largest water cave in the world. Inside this enormous cave there are multiple water strings and a lake that has made the cave only accessible by boat. Depth of water reaches 14 meters at some places in the cave. The temperature of the cave is fixed at 14 degrees Celsius all year long. The cave is millions of years old and its age goes back to Jurassic period. It is interesting to know that due to lack of sunlight there are almost no living creatures in the cave Except unicellular organisms and algae and a rare species of crustaceans. The cave has many stunning views and lakes and pure water that takes your breath away. The water is so transparent that one can see to the depth of 10 meters with the naked eyes and ordinary light.

More than 11 kilometers of the cave's water canals have been discovered so far. Some routes are 10 to 11 kilometers long and all lead to "The Island", a centrally located large atrium.

The cave was originally discovered during the reign of Darius I (521-485 BC) which can be verified by an old inscription at the entrance of the tunnel. However, the knowledge of the existence of the tunnel was lost, and only rediscovered in 1978 when a local shepherd who followed the tunnel searching for water or a lost goat.