The European Sauna Marathon includes 19 freezing ice baths, hot tub dips, and steamy saunas. It may support a key 'third pillar' of physical fitness.

REUTERS/Ints Kalnins

A man takes a dip in the cold water during the sauna marathon near Otepää, Estonia on February 2, 2019.

• The European Sauna Marathon takes place during one of the coldest winter afternoons every year in Estonia.
• Teams of four compete for the grand prize: their own hot tub.
• The "SaunaMaraton" is not so much a sporting event as it is a chance to eat, drink, and chat in the midst of the dark, cold days of winter.
• There's also a growing pile of evidence that suggests the exposure to steamy hot saunas and frigid cold plunges is good for health.

Surviving cold, harsh winter temperatures is a marathon, not a sprint.

That's certainly true in Estonia, where every winter people from around the world gather for the annual European Sauna Marathon in Otepää.

The goal is to make some of the coldest days of the year a little brighter.

February is the coldest month of the year in the tiny Northern European country on the Baltic Sea. Temperatures during the competition consistently hover below freezing, at around -6 Celsius (in the 20s Fahrenheit.) This year was no exception. On February 2, thermometers in the tiny town of less than 4,000 people topped out around -1 Celsius (30 F).

The Sauna Marathon is not a true 26.2-mile marathon; the only real running competitors do here is to and from the saunas.

Instead, it's a chance to bond with others who've braved the cold, often wearing little more than a robe.

"Many people think saunas are just hot rooms, but to Estonians they are so much more," marathon participant Adam Rang told Business Insider on Twitter.

It turns out that saunas may also provide some measurable health benefits, which, coupled with diet and exercise, could be considered a "third pillar" of physical fitness.

Here's a feel for what the race is really like, minus the chilly Estonian air.