This looks like the underground dwelling of the Tuatha de Danaan, or "Children of Danu", the mythological mother goddess of the Irish Celts. Creatures such as leprechauns and other Fairy Folk were known to inhabit these places, particularly under the burial mounds, which were also known as the fairy mounds for that reason.
German photographer Killian Schoenberger has utilized moody landscape and old stories of his childhood homeland to create a series of photographic illustrations inspired by the fairy tales of the Brothers Grimm. Shot in remote rural areas of Middle Europe dominated by images of haunting fog, gnarled trees and dark homes you hope are abandoned. His exemplary work as a photographer is made even more impressive by the fact that he is colorblind.
"Is it safe?" She asked, grabbing his hand. "Oh, sure...well...probably." He grinned. They peered into the doorway at the bluish glow. He stepped inside pulling her after him. "Here we are." He whispered. "This had better work." ~AM