Skijoring ('skē-jȯr-iŋ) is a winter sport where a person on skis is pulled by a horse, a dog (or dogs) or a motor vehicle. It is derived from the Norwegian word skikjøring meaning ski driving.
As you can see, in Leadville, they've taken this Norwegian idea and given it a Colorado spin. Notice also the rings on the ski jorers right arm. There's a bit of a jousting element added in as well.
For more pictures from the event in Leadville this past weekend, visit Summit Daily News.