The long-forgotten spires and domes of the drowned land of ancient Kalumesh were located off the coast of Cornwall, near the little town of Penmallow.
Kalumesh sank after being accursed by the Elder Ones, who represented good, and who abandoned its people to an evil cult. The people worshiped the Demon-God Dagoth, who served Shuma-Gorath.
That story was recounted in Von Juntz's Nameless Cults.
As a sunken city of ancient times, related to elder deities, Kalumesh is presumably inspired by Atlantis, Lemuria, and the Cthulhu Mythos.
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