Many know the story of Balto, but that’s only a small part of it. Balto ran the last 55 miles (85 km) to Nome, Alaska bringing a case of much needed antitoxin to cure the diphtheria outbreak that the men, women and children needed.
However the real hero of that story is Togo, a sled dog owned by Leonhard Seppala who bred and raced Siberian huskies. Togo was twelve years old when he traveled a total of over 261 miles (420.039 km) which was the longest and most dangerous part of the journey to deliver the antitoxin.
To quote Seppaia in 1960, "I never had a better dog than Togo. His stamina, loyalty and intelligence could not be improved upon. Togo was the best dog that ever traveled the Alaska trail."
I highly recommend looking up Togo and his story online or watching the movie based on this four legged hero.