This cavernous 3,000-square-metre spa by DecaArchitecture is located within a building that is carved into the base of a mountain in Mystras, Greece.
Billed as the first holistic wellness destination spa retreat in Greece, the Euphoria spa sits between a cypress forest and the UNESCO World Heritage Site of Mystras ? an important Byzantine landmark.
Its dramatic interior has been shortlisted for a Dezeen Award in the Leisure and wellness interior category.

"The Euphoria Spa is 3,000 square metres of varied and carefully articulated experiences. It is meant to be at the same time peaceful and subversive, meditative and hallucinatory, orderly and free-flowing," said DecaArchitecture.
"This occurs through a choreographed transition of spaces in which light, sound, temperature, humidity, textures, materials and smells create immersive sensory experiences."
At the base of the four-storey building, the spa's reception, underground treatment and consultation rooms, and changing facilities are spread across a series of elliptical spaces of various different scales connected by a network of catacomb-like passages.
Three concentric cylinders punctuate the building. The inner circle is a white 20-metre-deep light well, which opens to the sky and serves as a directional beacon.

A stairwell rendered in grey exposed concrete spirals around the central lightwell winding upwards though the building's four storeys.
As visitors ascend upwards a series of landings with a...