SARKEL

The mystical fortress Sarkel was located somewhere between the Don and the Volga. Moreover, the fortress site itself is considered to be flooded today. Please note that the word "sarkel(i)" may represent a Kartvelian adjective ending in "-eli" from the root "sarke", which means "mirror" in Georgian. If this hypothesis makes sense, then the name of the fortress is read as "mirror". A perfect name for a fortress on a bank of a river with reflection in water...