HISTORY OF PACK BURRO RACING
There are two legends concerning the beginning of these burro races. The first states that the races began when two miners found gold in the same location at the same time and had to race back to town to get to the claims office first. Because they could not ride the burros (the burros were either too small or loaded down with supplies), the miners were forced to run, leading the burros. The second legend is somewhat vague but concerns a few drunken miners at a bar in Leadville, Colorado. Pack burro racing is a sport indigenous to the State of Colorado which is deeply rooted in the state's mining heritage. In the early days of the mining industry in Colorado, miners would take burros, which is the Spanish word for donkeys, through the mountains of Colorado while prospecting. Because the burros were carrying supplies, the miners could not ride the animals and so they would walk, leading the donkey. The Burro Races, which are held throughout small towns in Colorado, commemorate these men and women and their burros. In 2012, Pack burro racing was recognized as the official summer heritage sport in Colorado.
 Source Credit: Wikipedia Article Pack burro racing