The Marathon covers the entire Medicine Bow Rail Trail and includes a singletrack path around Lake Owen. Go here for more information.
The Half Marathon starts with a lap around Lake Owen, then an out-and-back on the Medicine Bow Rail Trail, followed by another lap around Lake Owen. Go here for more information.
For more information on the Rail Trail including history, fire scars, and general information go to the Friends of the Medicine Bow Rail Trail website.