Therme Vals, Switzerland

Thermal water pours from curved spouts into the outdoor pool at Therme Vals as snow covers the Graubünden mountains behind. Peter Zumthor built the bath from about 60,000 slabs of local Valser quartzite, and it opened in 1996. Water from the St. Peter spring emerges at about 30°C (86°F), and the outdoor pool is heated to around 36°C (97°F) in winter. It is as much a building to experience as a place to soak.