Icebound
Nome lies just two degrees south of the Arctic Circle, and while greatly diminished from its peak of 20,000 during the gold rush days at the turn of the 20th century, it was still the largest town in the northern half of Alaska in 1925 with 455 Alaska Native and 975 settlers of European descent. From November to July, the port on the southern shore of the Seward Peninsula of the Bering Sea was icebound and inaccessible by steamship, and the days shortened with the onset of the polar night.
The only link to the rest of the world during the winter was the Iditarod Trail, which ran 938 miles (1,510 km) from the port of Seward in the south, across several mountain ranges and the vast Alaska Interior before reaching Nome. While within a decade bush pilots would become the dominant method of transportation during the winter months, the primary source of mail and needed supplies in 1925 was the dog sled.
Mail from the "Outside" (outside the Alaska Territory) was transported 420 miles (680 km) by train from the icefree port of Seward to Nenana, and then was transported the 674 miles (1,085 km) from Nenana to Nome by dog sled, which normally took 25 days.
Read more about this topic: 1925 Serum Run To Nome