1911 Encyclopædia Britannica, Volume 15… (1911)
“ In later Byzantine times it was an important frontier station, and did not pass into Ottoman hands till twelve years after the capture of Constantinople. The town, altitude 4860 ft., is built round the foot of a lofty rock, upon which stand the ruins of the Byzantine castle, Maurocastron, the Kara Hissar Daula of early Moslem chroniclers. ”
