BOULDER, Colo. (CBS4) – Two University of Colorado students wearing tennis shoes, shorts and T-shirts were rescued Friday from the first Flatiron outside Boulder.

A nearby climber heard them calling for help and called 911 at 6 p.m., according to the Boulder County Sheriff’s Office.

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Members of the Rocky Mountain Rescue Group rappelled down to the pair that was stuck two-thirds up the Direct East Face route.

The two students were secured and outfitted with proper gear, then escorted up to the top of the rock and down the western side.

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The duration of the rescue was two hours and 40 minutes, per BCSO.

Boulder Flatirons (credit: CBS)

The iconic series of slabs are known for their quick access and beginning to intermediate difficulties of climbing terrain.

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“The Flatirons are synonymous with Boulder and the history of rock climbing in North America,” according to the MountainProject.com website. “It would be hard to find another location in the country where such an extensive variety, from scrambling to hard ‘Head Point’ routes, exist so close to a major metro area.”