And with strange aeons even death may die."
-- Abdul Alhazred (HPL)
In an extract from the Necronomicon given in The Dunwich Horror, he is described as their cousin... yet he can spy them only dimly. Elsewhere, he is described as the 'High Priest' of the Great Old Ones, being an alien of gigantic proportions who lies 'in death's dream' with the others of his race in the submerged city of R'Lyeh, in the Pacific ocean. When 'the Stars are right', R'Lyeh will emerge from the deeps, heralding the beginning of the return to Earth of the Great Old Ones. When Cthulhu stirs, a telepathic ripple is transmitted across the world, causing sensitive subjects to go mad, or to capture fragments of the vision in words or images.
Cthulhu's city-tomb, R'Lyeh, is composed of 'non-Euclidean Geometric forms' - strange angles and perspectives which also appear (in the story The Dreams in the Witch-House) as gateways to the outer dimensions.- Phil Hine (Prime Chaos '93 p101)
Pix taken from: http://easyweb.easynet.co.uk/~phodges/Pages/home.html