Buried deep within the rugged alpine slope of the Valsertal in Graubünden, the Vals Thermal Pavilion Study explores the elemental communion of mineral water, rock, and subterranean space. Rather than a building resting on the ground, the pavilion is an excavated labyrinth carved directly into ancient gneiss bedrock. The structure is built from 60,000 precision-cut blocks of local grey Valser quartzite, laid in varying horizontal courses that mirror the geological stratification of the surrounding mountains. Submerged bathing caverns of varying temperatures—from a 14°C cold plunge to a 42°C steam pool—are linked by narrow stone corridors where the sound of cascading thermal springs echoes softly off damp stone walls. Illumination is introduced exclusively through slender 8cm ceiling fissures sliced into the green roof above. As daylight filters down through rising plumes of mineral vapor, it animates the glistening mica flecks in the quartzite walls, creating an archaic, reverent atmosphere that suspends all sense of modern time.