At the Mountains of Madness is a science-fiction and cosmic horror novella by the American author H. P. Lovecraft, written in February–March 1931 and published in three installments in 1936.
The story details the events of a disastrous expedition to Antarctica in September 1930, and what is found there by a group of explorers led by the narrator, Dr. William Dyer of Miskatonic University.
