A hiss cracks into a roar, and I feel the heat seconds after the water slowly winds its way through the stacked stones. It comes with such force I feel like I’m almost knocked backward, even though I have tucked my head into my chest, bracing for impact.

Löyly, a Finnish word with no direct English translation, comes in full. It has ancient roots in Finnish folklore as the “spirit of life,” the soul of the sauna, beyond the steam itself. We’ve spent the day conquering singletrack, and yet this scorching steam rising from volcanic rock is conquering us.

“How do the Finnish do this?” I hear photographer Leslie Kehmeier call out somewhere beside me into the pitch-black, windowless room, its walls charred from years of smoke.

There’s no chimney in the Karsikkolampi smoke sauna, a cultural highlight of the village of Syöte. There never has been. This original method takes almost eight hours, and the fire burns continually. Smoke fills the room, heating the stones and blackening the log walls, until someone decides it’s time to let it out. The history of this bathing ritual spans 10,000 years. Now, it is a cultural cornerstone of Finland—a sacred, communal space used for bathing, healing, childbirth, and even preparing the dead.