Cadmea

The Cadmea, or Cadmeia, was the citadel of ancient Thebes, Greece, named after the legendary Phoenician founder of Thebes, Cadmus.The area is thought to have been settled since at least the early Bronze age, although the history of settlement can only be reliably dated from the late Mycenaean period onwards.
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zinc oxide| calamine; dross/slag formed in a furnace (L+S); citadel of Thebes