Primate Quest: The streets of Denver become planet of the apes during the annual Gorilla Run. 

The notorious cruiser bike rides in Boulder and Denver always call for a costume—the gaudier the better. But come the spooky season, the Front Range offers many more opportunities to get sweaty in costume—preferably your Halloween costume. Or in the case of the Denver Gorilla Run, a full gorilla suit. So round up your most outrageous attire, make sure you can run in it, and read on for our favorite events.

BOULDER CRUISER RIDE
Thursdays • Boulder
It’s like Halloween on bikes every Thursday night in Boulder thanks to a costumed cruiser ride that attracts hundreds. Not only are the riders decked out, but also their rides – beads, lights, tassels and bells are the standard – on every type of bike from vintage 1950s Schwinn’s, to giant tricycles. The costume theme changes every week, check the website for details.
cruiserbikeride.org

DEVIL DASH
Oct 8 • Lyons
Costumes aren’t required at this “hellish” 5k-adventure race featuring obstacles inspired by the seven deadly sins including cargo nets, crawling through mud pits and darting through fire, but they are highly encouraged. The promoter also recommends wearing a costume that you don’t mind “getting muddy and bloody.”
devildash.com

SCREAM SCRAM RUN
October 21• Denver
This Friday night 5k-run/walk around Wash Park caters to witches, ghouls and ghosts. It’s a fundraiser for the Denver Metro Girls and Boys Club, so consider signing up as a “scream team” with your friends or family. If you’re not in costume, don’t bother trying to hit up the Trick or Treat Street bonanza near the finish line, you big scrooge.
bgcmd.org

DENVER GORILLA RUN
October 29 • Denver
You can tackle this 3.5-mile course through the heart of Denver by foot, bike, rollerblade, skateboard or even unicycle –so long as you’re outfitted in a full gorilla suit. You get to keep the costume, which is included in your $99.95 entry fee. Put it on and chase your dog around the neighborhood. See if anyone notices.
denvergorillarun.com

HALOWEEN 5K
October 29 • Boulder
For the second year, the CSU Triathlon Team is hosting a costumed-5K at the CU Oval just in time for Halloween. If the weather is warm, expect to see some of Colorado’s finest physiques scantily clad in costumes that would make your grandmother cringe. If it’s cold, well, at least you got a good workout in before mass candy consumption.
csutri.com

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