The Ralston Creek Half Marathon and 5K are back in 2024 and we are excited to announce the Racing Underground Winter Running Series also returns in 2024! Join us at Colorado’s Premier Winter Half Marathon. The Ralston Creek races feature a fun winter half-marathon and 5K run conveniently located on the west side of the Denver Metro Area in Arvada, Colorado. The courses covers a scenic mix of road and bike path over rolling terrain, and an optional early start time for half-marathon runners who expect to take more than 2.5 hours to complete the course! HALF-MARATHON COURSE:The Ralston Creek Half Marathon course follows a mix of roads and bike paths on the west side of Arvada. The opening 5 miles are fairly flat, with a barely noticeable gradual gain in elevation. Miles 5 through 6.5 are rolling, with one good climb leading to the high-point of the course atop Ralston Mesa at 7.75 miles. From there, the course is almost all downhill and flat to the finish, with the exception of a small bump around mile 9 and a very gradual uphill in the last half-mile.