Triermain Castle
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Triermain Castle was a castle in the civil parish of Waterhead, near Brampton, Cumbria, England. Triermain, Cumbria (Trewermain, Treverman c 1200): 'homestead at the stone' (Welsh tre(f) y maen)
It is featured in Samuel Taylor Coleridge's famous poem "Christabel" where the changeling Geraldine is apparently the daughter of Sir Roland de Vaux of Triermain.