This is also known as historical-natural cave because of having hand-made connected rooms as well as natural halls that dates back to the 3rd Geological age. It has been found in middle of 20th century by American travelers and later on, they commerce to study about this ancient cave and troglodytes who have been living in this cave for about 15000 years.
It is well noted that hieroglifies of those people are well preserved that have been excavated by Russian archaeologists over the past decades. Most of these hieroglifies are in 3rd floor & entrance of first floor that maintained by Mr. Khanikov.
The hand-made rooms of this cave are in 4 floors that have been used a Solukids and were expanded by Parthians in about 2200 years ago. In Sassanian dynasty, function of this cave was changed into a holy temple apart from being a castle and it had become a sacred place for Zoroastrians back then.
It has been used until Mongolians invaded Persia and later on it got abandoned for centuries. As a travel consultant we would highly recommend to take a guided tour of this ancient-holy cave to get acquainted with its water system as well as its extraordinary design by taking a day trip from either Zanjan or Sanandaj.