Image credits — all photos sourced from Wikimedia Commons under Creative Commons licenses.

hero-heater.jpg
  Source: https://upload.wikimedia.org/wikipedia/commons/thumb/0/05/Harvia_Ventura_sauna.jpg/1920px-Harvia_Ventura_sauna.jpg
  Harvia Ventura sauna (Wikimedia Commons, CC BY-SA 4.0)

interior-modern.jpg
  Source: https://upload.wikimedia.org/wikipedia/commons/thumb/4/45/Clarion_Hotel_Helsinki%2C_Sauna%2C_20231215_-_03.jpg/1920px-Clarion_Hotel_Helsinki%2C_Sauna%2C_20231215_-_03.jpg
  Clarion Hotel Helsinki Sauna (Wikimedia Commons, CC BY-SA 4.0)

interior-classic.jpg
  Source: https://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Finnish_Sauna_Society.jpg/1920px-Finnish_Sauna_Society.jpg
  Finnish Sauna Society (Wikimedia Commons, CC BY-SA 3.0)

finnish-sauna.jpg
  Source: https://upload.wikimedia.org/wikipedia/commons/thumb/4/4b/Finnish_Sauna_-_panoramio.jpg/1920px-Finnish_Sauna_-_panoramio.jpg
  Finnish Sauna (Panoramio, CC BY 3.0)

smoke-sauna.jpg
  Source: https://upload.wikimedia.org/wikipedia/commons/thumb/4/4a/Smoke_sauna_-_panoramio.jpg/1920px-Smoke_sauna_-_panoramio.jpg
  Smoke sauna (Panoramio, CC BY 3.0)

smoke-stove.jpg
  Source: https://upload.wikimedia.org/wikipedia/commons/thumb/d/d4/Rauchsauna_ofen.jpg/1920px-Rauchsauna_ofen.jpg
  Rauchsauna ofen (Wikimedia Commons, CC BY-SA 3.0)

outdoor-cabins.jpg
  Source: https://upload.wikimedia.org/wikipedia/commons/thumb/4/4a/Finnische_Blocksaunen_%28Au%C3%9Fensauna_Rheinhessen-Bad%29.jpg/1920px-Finnische_Blocksaunen_%28Au%C3%9Fensauna_Rheinhessen-Bad%29.jpg
  Finnische Blocksaunen (Wikimedia Commons, CC BY-SA 4.0)

spa-room.jpg
  Source: https://upload.wikimedia.org/wikipedia/commons/thumb/8/8f/ITA_Brunico%2C_Hotel_Falkensteiner_009.jpg/1920px-ITA_Brunico%2C_Hotel_Falkensteiner_009.jpg
  Hotel Falkensteiner sauna (Wikimedia Commons, CC BY-SA 4.0)

bench.jpg
  Source: https://upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Bastun%2C_Mariehamn.jpg/1920px-Bastun%2C_Mariehamn.jpg
  Bastun Mariehamn (Wikimedia Commons, CC BY-SA 4.0)

showroom.jpg
  Source: https://upload.wikimedia.org/wikipedia/commons/thumb/3/3d/Harvia_showroom_in_Muurame%2C_Finland.jpg/1920px-Harvia_showroom_in_Muurame%2C_Finland.jpg
  Harvia showroom (Wikimedia Commons, CC BY-SA 4.0)