The 300 Club is a small number of individuals who have endured a temperature difference of 300° Fahrenheit (166 °C) within a very short time. The group originated at Amundsen-Scott South Pole Station in Antarctica, and has since been established in North America.
Participants in the Antarctic 300 Club wait for a day when the temperature drops to −100 °F (-73 °C) for more than a few minutes, generally in the winter. They first warm up in a sauna heated to 200 °F (93 °C) for as long as 10 minutes. Then they run naked to the Geographic South Pole, circling it in the −100 °F weather. After this, they usually warm up in the sauna again, often with the aid of alcoholic beverages.The first 300 Club outside of Antarctica was established on January 30, 2019 near Minneapolis, Minnesota during a polar vortex. With an outside temperature of −27 °F (−33 °C), three men heated their backyard sauna to 280 °F (138 °C) and sat inside for 10 minutes. Upon exiting the sauna, they sprinted around a flagpole planted in honor of the South Pole tradition, and took a brief roll in the snow before returning to the sauna.There are several patches made to commemorate the occasion that are entitled to be worn by those who have joined the 300 Club.