Summer Sizzler- Denver
- Date
- August 8, 2026
- Distance
- Kids Dash · 1 Mile · 5k & more
From the Organizer
Join us for the annual Summer Sizzler 5k/10k/15k! A fun summer event that is perfect for the whole family.
The fun includes -
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Great Swag - designer shirt & custom medal
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Chip-timing with live results and awards
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Free photos
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Delicious Treats waiting at the finish line
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FREE Shaved Ice!
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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!
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5k/10k/15K registration includes a custom bib, designer shirt, and a custom finisher medal!
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1 Mile registration is untimed and includes a custom bib, designer shirt, and a custom finisher medal!
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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!
Events
Weather
Typical Conditions
It's too far out for a forecast, so here's what weather on this date is normally like in the area. A race day forecast will replace this as race week approaches.
Typical High
90°
Typical Low
59°
Chance of Rain
26%
Based on US Climate Normals data from Northglenn, 3 mi from the venue.
Host City
About Thornton, CO
Population
142,878
as of 2023
Elevation
5,347 ft
Nearest Airport
DEN
Denver International Airport · 16 mi
Time Zone
Mountain Time
From Endurance Grid
A mid-size host city. Enough lodging and amenities to keep race weekend easy, without big-city sprawl.
Race Location
Your Next Start Line
What Are You
Waiting For?
Every finish line starts with a single decision. Claim your spot at Summer Sizzler- Denver, put it on the calendar, and turn “someday” into a start date.
61
Days to train
- Race
- Summer Sizzler- Denver
- Date
- August 8, 2026
Coming Up
More Running races near Thornton, CO
Treat Trot - Denver
Less than a mile away
Unicorn 5k (North)
5K
Less than a mile away
All-Out Dog Days
4 miles away
RMRR September 5k/10k
10K · 5K
Less than a mile away
From Endurance Grid
About This Sport
Endurance Grid is here to help you understand the sport, decide if it's the right fit, and learn how to prepare. For course distances, logistics, and race-day specifics, always defer to the race organizer's event page.
With running, there's a distance for every fitness level, a community at every start line, and nothing beats the feeling of crossing a finish line you trained for.
Running is an endurance sport that rewards consistency, and showing up every week compounds in ways that will surprise you.
Running
From 5K to marathon, running races are the most accessible entry point into endurance sport. There's a distance for every fitness level and a community at every start line.
Frequently Asked Questions (FAQs)
- What is the Summer Sizzler- Denver?
- Summer Sizzler- Denver is a running race held in Thornton, Colorado on August 8, 2026. It is one of the many endurance events listed on Endurance Grid, a multi-sport endurance event calendar covering running races, triathlons, HYROX, and more endurance sports across the United States. Find more running races near you or explore our sports guides to learn what race day actually feels like.
- When and where is the Summer Sizzler- Denver?
- Saturday, August 8, 2026 in Thornton, Colorado at Carpenter Park/Thornton Recreation Center Park, Thornton, CO. Check the event page for exact start times and wave schedules.
- How do I register for the Summer Sizzler- Denver?
- Registration is handled through the event's registration page. Confirm pricing and distances there, and sign up.
Summer Sizzler- Denver
Aug 8, 2026