Yezud

The citadel-city of the spider-god, Zath, is located on Mt Graf in the Karpash mountains of Zamora. It sits atop a crag on the mountain and is considered to be impregnable. The spider idol was of stone, worshipped by dancing girls clad in black beads. (Conan and the Spider God, Thing in the Crypt, Castle of Terror, People of the Black Circle)