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.
No this isn't a fairytale. This is Ryokan Sangaa magical inn with the most gorgeous onsens (natural hot spring fed baths) where @thedenizenco & I hosted our second annual wabi sabi inspired photography retreat. We called it home for a week & my heart aches for these paths already. Every other place pales in comparison. If you want to join us here next year you can join the retreat mailing list at localmilkretreats.com #wabisabiworkshop #localmilkretreats #ryokansanga by local_milk