The Larimer County Coroner says Audra Brownell of Sparta, Mich. died at the scene after she was hit by a falling rock at about 3:40 p.m. on Thursday.
Brownell belongs to the Rockford Reformed Church in Michigan. According to the church's website, one of its youth groups was visiting Estes Park on a backpacking trip.
The town of Estes Park says the incident occurred in the Knoll-Willows open space, and that area is closed to the public.
"The community is devastated by this tragic incident and our thoughts are with the family and friends of the victim," Estes Park Mayor Bill Pinkham said in a news release. "Our police department is working around the clock to sort out the details of the incident."
Officials say they are interviewing witnesses about what happened, and a civil engineer is surveying the area to check for other possible falling rocks.
Town workers have also started constructing a temporary fence around the area.
"The town is taking precautions in the safety of this area ... to make sure that we protect the safety of our residents and our visitors, that's our first priority," Katie Rusch, spokesperson for Estes Park, said.
Local residents expressed surprise after hearing about the incident.
"I've never heard of anything like this happening before," Taury Bailey, who grew up in Estes Park, said.
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