Arthur Machen 
The Shining Pyramid 

Strange arrangements of stones appear at the edge of a young man’s property. When he and a friend attempt to decipher their meaning, they uncover something ancient dwelling deep underground – something best left untouched … Originally published in 1895, this classic tale of subterranean prehistoric entities was acclaimed by genre legends such as H. P. Lovecraft and Robert E. Howard, so much so that the latter would later write and publish a sequel of sorts – 'The Little People’ – in 1970.