DoNot Stop Half Marathon (5k/10k) - Denver

Get ready for a sun-soaked adventure and a fantastic mid-season challenge with our 13th Annual Dog Days 5K, 10K & Half Marathon, benefiting Do Over Dogs! Held in a central location between Denver and Boulder, our courses wind northeast along the scenic Big Dry Creek Trail. As you run, you’ll enjoy breathtaking views of the Flatirons on the horizon. Our trail is perfect for dogs, featuring a generous amount of soft surface along the 10K and half marathon routes. Plus, we have a special dog division to award the fastest pups at each distance and a dog-themed costume contest for extra fun! And continue the challenge by participating in the endless series counterpart, Fa La La, in December.

Join us for the annual Summer Sizzler 5k/10k/15k! A fun summer event that is perfect for the whole family.

The fun includes -

• Great Swag - designer shirt & custom medal

• Chip-timing with live results and awards

• Free photos

• Delicious Treats waiting at the finish line

• FREE Shaved Ice!

• Plenty of fun!

Grab your friends and family, you are not going to want to miss this one!

Can't make the race? No problem! We offer a virtual race option where you can run anywhere, at any time, and still earn the fun swag!

*Youth-based pricing for the 5k/10k, 12 & Under are only $17!

• 5k/10k/15K registration includes a custom bib, designer shirt, and a custom finisher medal!

• 1 Mile registration is untimed and includes a custom bib, designer shirt, and a custom finisher medal!

• The kid's dash is a fun, untimed dash for our kiddos ages 10 and under. Registration includes a mini bib, youth-sized shirt, and a specifically crafted medal for our kids' dash event! (If your child wants to run the kid's dash, and doesn't want the SWAG, they are welcome to run with us on race day for free!)

*Register by midnight on Thursday, two Thursdays before race day, to guarantee your shirt!

🏁🏅Create a team, or join an existing team during registration. Once 4 people have registered on that team, all team members will be refunded $5, once ten people register another $5 will be refunded for a total of $10!

Rocky Mountain Road Runners holds a monthly Trophy Series in the Denver area. We provide a low-key, low-cost racing environment. Everyone is welcome to run with us!

The 10km race uses a handicap start system, slow-to-fast, spread over ~30 minutes. This gives everyone a chance to win. We'll use your estimated finish time to assign you a start time with others the same speed.

All 5k racers will start ~15min after the first 10km starters.

Race Day Details

Time: 10k starts at 8:00 am + your handicap.*

5k starts approximately 15min after the first 10k starter.

Show up 30 minutes early to get your tag and warm up.

Location: Riverdale Ballfields, 9830 Riverdale Road, Thornton, Colorado, 80229

Course: Both distances are out-and-back on a mix of paved and smooth gravel.

Parking: Plenty of parking at the park.

• The Trophy Series races use a unique, handicap start and scoring system. 10k racers start from slow to fast giving everyone a chance to win. When you register and pick up your number, we'll help you choose an appropriate start time that fits your estimated time.