Loyly Sauna, Helsinki

Finland is so famously flat that Norway launched an online campaign last year to give its neighbour one of its many peaks.

But what the country lacks in height, it makes up for with saunas: There are 3.3 million of them, roughly one per household. But when Loyly, a commanding new structure built along the edge of the Baltic Sea, opened in May, it became Helsinki’s first true public sauna.

It has all the hallmarks of a true sauna, which until now have been relegated to Finns’ homes: It is heated by wood, features smoke and has an accessible body of water to jump into at the end. Jasper Paakkonen, a Finnish actor, avid environmentalist and partner in the project, thinks of the shell-like design as a “tunturi,” the Finnish word for something that’s between a hill and a mountain.

The word loyly translates as the steam radiating from the rocks when you throw water on the hot stones in the sauna. In Old Finnish, it also means “spirit” or “life.”

“Sauna is an essential place for cleansing and purifying our minds and bodies,” Paakkonen says. “In Finland, it’s not a luxury. It’s a part of everyday life.” No cellphones will be allowed in any of the three saunas, as it’s generally considered a quiet place where the Finns go to practice omissa oloissaan, or aloneness with one’s thoughts.

The original design for the Avanto Architects project — located in a formerly open stretch of land in Hernesaari, a small peninsula in Helsinki that is transitioning from an industrial to a residential area — was so ambitious, construction companies wouldn’t even provide a quote.

“We loved it so much, we tripled the budget,” Paakkonen says, referring to Antero Vartia, his business partner and a member of Finnish Parliament. The duo also worked with Nextimber, a start-up technology that converts waste wood into wood panels, to make the building as environmentally friendly as possible.

As a result, Loyly is the first project in Finland to earn certification from the Forest Stewardship Council.