H.P. Lovecraft's The Nameless City.

Deep in the Arabian desert lie ruins ancient beyond all the cities of men. The Arabs shun them, but one man finds himself drawn to them, seeking them out with the help of only his camel, to uncover the dark and horrible truths hidden therein. The Nameless City is widely regarded as the first of the real Cthulhu Mythos tales, and introduces Abdul Alhazred...