It seems very strange to me to interpret this building as a water tank. In the same fortress of Naryn-Kala, there is an equal underground structure of 10 meters depth, and it really is a tank. This is just a rectangular building. The unusual building, in which we have put our detectors, has the shape of a cross, oriented strictly to the sides of the world, one side is 2 meters longer than the others, as the archaeologists who began excavations say, during construction, the building was entirely on the surface and it stands on the highest point of the Naryn-Kala. What is the sense to put the tank on the surface, and even on the highest mountain? It is strange. Currently, there are more questions than answers.