More than 120,000 people were expected to be in Boulder on Memorial Day for the Bolder Boulder.
The 10K is known as the fifth largest race in the nation.
This year 50,765 people, including eight athletes that will go on to compete in the Rio Summer Olympics, signed up for the race.
About 70,000 people were expected to line the race route to watch the runners, many of whom race in wild costumes.
I love the costumes and shirts this year! @bolderboulder @DenverChannel pic.twitter.com/FlETsyDTFo
— lisa hidalgo (@LisaDenver7) May 30, 2016
Participant Lauren Trede and her supporters are wearing Wonder Woman costumes. Trede was hit by an SUV a year and a half ago and was left in a wheelchair. She transitioned to a walker, then to hiking poles, then to walking with a cane, and can now walk unassisted. She said she's been able to walk about three or four miles and hopes to finish the 10K (6.2 miles) in about two hours.
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The race began a little before 7 a.m. with a race for joggers, runners and those in wheelchair.
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At around 11:15, the international pro-race began with runners from places like Kenya, Brazil and Mexico competing.
The fastest anyone has ever completed the race was 27:52. That record was set by Josphat Machuka in 1995.
Along the route you'll find live music and entertainment options.
My favorite band so far... @bolderboulder pic.twitter.com/hGL0BQ5gBD
— lisa hidalgo (@LisaDenver7) May 30, 2016
"We pack the course so you never quite know what’s around the corner," the website states.
Slip-n-slide and Jell-O shots at mile 1. #NoThankYou #Still5ToGo @bolderboulder @DenverChannel pic.twitter.com/Kx9DSISPhq
— lisa hidalgo (@LisaDenver7) May 30, 2016
For the first time this year, that race will begin closer to Folsom Field, on the corner of Taft and Folsom Street.
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The race finished at Folsom Field a little after noon was followed by a Memorial Day tribute service.
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