In Finland, it is estimated that there are 3.5 million saunas. They even exist in fast food restaurants. And no steam is left unexplored with guide Samuel Aarnio, who represents a younger generation that holds fast to the centuries-old sweat bathing tradition. Samuel and Mikkel start their sauna adventures in Helsinki and venture outward, island hopping by boat, visiting old friends for a traditional smoke sauna, and testing their limits in 60+ saunas at the Mobile Sauna Festival in Teuva. They even discover new ways of cooking meals by sauna, and indulge in the purity of a remote sauna village, deep in Finland's countryside.