Reindeer
From around 1899 reindeer were used to deliver mail in Alaska for the U.S. postal service. The first route was established by Sheldon Jackson and ran from St. Michael to Kotzebue, with another managed by William Kjellmann going between Unalakleet and Nome. Distances of 30–50 miles were covered by the service, with the reindeer carrying up to 300 pounds (140 kg) of mail.
Read more about this topic: Mail Delivery By Animal