Thought of as a mix between Mongolian or Thoroughbred, Sergeant Reckless defined what it meant to be a true hero. Bought by the United States Marine Corps in 1952, this mare carried supplies and weapons to soldiers and even excavated wounded ones from battle during the Korean War. She was not only fast, but could memorize a trail after only a couple of trips, which meant she often travelled solo. In March of 1953, she made 51 supply trips to soldiers on the front line in a single day. She earned two purple hearts and a Good Conduct Medal for later service. LIFE Magazine selected her as one of the 100 All-Time Heroes.