The Haunted Half - Salt Lake
This is Utah's party run, featuring one of the best courses in the state, a scenic half marathon that starts at 6200 feet in altitude and runs down to 4400. It's fast, and a heck of a lot of fun. There is also a 5k and a kid's run.
The half marathon is point-to point, starting in Emigration Canyon and rolling down to Sugar House Park.
The 5k happens in Sugar House Park and features a costume contest. Bring the whole family as there is also a half-mile race for those 12 and under.