Denver's biggest running event will be bigger than ever. The Denver Colfax Marathon will feature eight races over two days: Saturday, May 18, and Sunday, May 19. The weekend's events include a marathon, half-marathon, 10 miler, 5K and the nation’s largest marathon relay. Organizers of the Denver Colfax Marathon said two race lengths have sold out and others are nearing capacity. The half-marathon and urban 10 miler races are sold out for 2024. There are spots left in the marathon, marathon relay and 5K. More local videos here: https://youtube.com/@9news Subscribe to NEXT: https://youtube.com/@Nexton9NEWS Stay connected: 9NEWS Website: https://www.9news.com/ Facebook: https://www.facebook.com/ilike9news Twitter: https://twitter.com/9NEWS Instagram: https://www.instagram.com/9newsdenver/ Download the 9NEWS App: https://www.9news.com/appredirect/ Sign up for the 9NEWSLETTER: https://www.9news.com/email 9NEWS (KUSA) is located in Denver, Colorado.