In addition to the main event, a half marathon, a relay and a new 5K race also take place. The 2011 Kaiser Permanente Colfax Marathon, Half Marathon and 5-person Marathon Relay were held on Sunday, May 15, 2011. Start and finish points were in Denver’s City Park. In between, the new marathon and relay course hit all the high points: vibrant Colfax, the Capitol, downtown, Cherry Creek Trail and Confluence Park, Invesco, plus eclectic, artsy neighborhoods in Lakewood. Runners loved the half-marathon course through Denver and Aurora: flat, fast and shady.