Classic horror story by H. P. Lovecraft. It is written as a narrative by a professor who is trying desperately to dissuade a forthcoming expedition to Antarctica.

It makes very good reading, quite possibly Lovecraft's finest work, and an excellent resource for students of the Cthulhu Mythos, as one can find a good load of background information on many of the creatures therein.

It can also be found as an audio book, where the narrative has been converted to a radio interview instead. It's a bit shorter than the book, but still not bad.