Boyd Lake State Park, CO.  Join us for a family fun event with 4, 7 or 10-mile race options. What’s a “Narrowleaf” you ask? The Narrowleaf Cottonwood Trees are the most densely populated tree species at Boyd Lake State park. This course is on perfectly paved walkways with about a half mile being off road on the south loop. No vehicle traffic to worry about and fun post race festivities. Did we mention almost no elevation gain?