Polar Circle Marathon
The Polar Circle Marathon is not only the most extreme, but also one of the most diversified marathons in the world. It takes place in September or October. There may not be another marathon on the planet that is as uneven and unpredictable as this one.
Participants start at the inland icecap near Kangerlussuaq and run over gravel roads and ice sheets, passing frozen lakes and the Arctic desert, greeting reindeer and musk oxen. Even the path becomes mountainous, and the temperature is constantly changing. In reality, due to its unevenness, the marathon takes at least a quarter percent longer to complete than other marathons.