About 45 km northeast of the city of Takab in West Azerbaijan is an ancient site that has hosted sacred structures among its fences since 1600 years ago.
The mystery of its lake have made it one of the most mysterious places in Iran. In addition to the beliefs that tell the secrets of this lake, the type of formation of the lake and its creation is also very interesting. Takht-e Soleyman which houses one of the three famous Sassanid fire temples and was the place of coronation of the kings of this dynasty, was built by Bahram V. The traveler of Takht-e Soleyman in addition of observing historical monuments in front of Khosrow Ivan, sees a lake that is 112 meters deep.
The Sassanid king, Bahram V ordered to built this area as a city and within 70 years, Ghobad I, another Sassanid king, expanded its buildings until that reached the peak of its greatness during the reign of Khosrow Anushirvan. Takht-e Soleyman is considered by many to be the birthplace of Zoroaster, and the construction of the Azargoshnasp fire temple in this area as the most important temple revered by Zoroastrian Iranians during the Sassanid era can be a seal of approval to this belief. This fire temple played an important role in the socio-political life of the Sassanid dynasty and its eternal flames were not extinguished for seven centuries to be considered as a symbol of the authority of Zoroastrianism.
Another popular belief also considers this city to be the residence of the Prophet Suleiman and points to the fact that extraterrestrial forces have built huge structures there by the order of Prophet Suleiman that humans cannot afford to build.
Takht-e Soleyman was destroyed in an attack by the Roman emperor in 624 AD and after centuries Agha Khan, the nephew of Holaku Khan, who had converted to Islam, built a mosque on the ruins of Takht-e Soleyman This mosque was also destroyed later and only tiles with patterns and embossed lines are left of it.
All the relics of Takht-e Soleyman are formed inside an oval fence and wall, and a wide plain surrounds it. The outer fence is made of stones of different dimensions with a thickness of 5 meters and a height of 14 meters and an external circumference of 1200 meters. The outer layer of the fence is decorated with cut stones and with 38 conical defensive towers. The building of the outer wall and fence belongs to the Sassanid period. In the Ilkhanate period, in addition to restoring some of the collapsed parts, a new gate was built next to the southern gate of the Sassanid era. In the northwestern part of the lake and at a larger square angle, a high porch called Khosrow porch can be seen and leads to two rooms or a hexagonal pool, which belongs to the Ilkhanate period.
The ancient complex of Takht-e Soleyman before Islam, was the largest educational, religious, social center and place of worshiping for Iranians. But in the invasion of Heraclius, the Roman emperor, was destroyed. This historical collection is the fourth Iranian work registered in the UNESCO list because it has works from several historical periods And from a mythological point of view, it is full of interesting content. This name is also given to this mountain according to the legend and according to the attribution of the place to Suleiman.