Read "At the Mountains of Madness" by H.P. Lovecraft online for free on Textopian. Full text with search, annotations, highlights, and AI-powered reading aids.
The full story, so far as deciphered, will eventually appear in an official bulletin of Miskatonic University. Here I shall sketch only the salient highlights in a formless, rambling way. Myth or otherwise, the sculptures told of the coming of those star-headed things to the nascent, lifeless earth out of cosmic space -- their coming, and the coming of many other alien entities such as at certain times embark upon spatial pioneering.
They seemed able to traverse the interstellar ether on their vast membranous wings -- thus oddly confirming some curious hill folklore long ago told me by an antiquarian colleague. They had lived under the sea a good deal, building fantastic cities and fighting terrific battles with nameless adversaries by means of intricate devices employing unknown principles of energy.