Gilgilchay Fortress, Azerbaijan
The powerful fortress occupied a vast area along the river Gylgilchai, went down to the Caspian Sea and up in the mountains. The fragments which have survived testify that it was a very efficient stronghold.
The walls were more than 6 meters thick and about 9 meters tall. There were numerous towers of about 15 meters tall placed 20- 30 meters from one another.
There have been found the remains of several forts adjacent to Gilgilchay wall. One of such forts was the size of a rather big ancient city.