In the Republic of Tuva, almost on the border with Mongolia, in the mountains at an altitude of 1300 meters above sea level is Lake Tere-Khol. Mountain pond, some in Russia can count thousands. But it is unique in that in the middle of it on the island are the ruins of an ancient fortress. Por-Bazhyn (Tuvan - "mud house") was built in the middle of the VIII century on the orders of the head of the Uighur Kagan Eletmish Bilge Kagan. In 750, he came up with the troops on the territory of present Tuva with a view to capture. In order to gain a foothold in the conquered territory, he built a fortress. Its walls reach a height of ten meters. The Central Palace, which stood on a high platform, belonged to Eletmish Bilge Kagan. Ancient builders had to make thousands of tons of clay and baked bricks. The monument has a complex architecture - inside the right rectangle is a maze of buildings, resembling a Buddhist or Hindu mandola.