Winter cycling in Alaska began in the 19th century — before the automobile, trains and even roads. In 1898, gold hungry men followed the frozen Yukon River from Dawson and rode to Nome on “wheels.” These hardy souls were known as “wheelmen” and they began a tradition that is alive in Alaska, over 100 years later.
Vast improvements have been made in all things winter cycling over the last 100 years, but none more important than the wheel itself. Four- and even five-inch tires open a world of possibilities for the winter cyclist.
Read more here: http://www.adventurecycling.org/resources/blog/fatbike-to-the-arctic-how-to-prepare/