A 26-year-old woman died after falling several hundred feet while free solo climbing in Colorado on Sunday.

The Boulder resident fell approximately 500 feet while climbing at Rocky Mountain National Park on the Four Aces of Blitzen Ridge, Fox News reported Tuesday.

“Blitzen Ridge is a technical climb which means you’re going up on a narrow ridge, and you’re sort of, as you’re climbing up, you’re encountering obstacles along the way. So, if you’re not roped, if you’re not tethered to another climber and you fall, there’s nothing to catch you,” a man with knowledge of the area told Fox 31.

Video footage from 2012 shows the rocky terrain and view from Blitzen Ridge on Mt. Ypsilon:

The Fox reported noted a 27-year-old man was climbing with the victim, and he contacted park rangers with a cell phone after the incident occurred. The park’s search and rescue team got to the man on Monday evening.

“The park requested help from a Colorado Air National Guard helicopter at Buckley Air Force Base to extricate the man, who was uninjured, via a hoist operation,” the outlet said. “The Rocky Mountain Rescue Group assisted in the effort and the rescuers used a winch operated cable.”

Once rescuers hiked to an area near Ypsilon Lake for a helicopter long-line recovery early Monday, crews transported the victim’s body to a helispot before taking her to the Larimer County Coroner and Medical Examiner’s Office.

Now, officials are working to determine an official cause of death, and her identity will be released once authorities can inform next of kin about what happened.

According to Climbing.com, the term free soloing refers to a person climbing without rope or gear:

The term free soloing is usually applied to steep and technical rock climbing done with only hands and feet, with the sole equipment being climbing shoes and chalk bag, but the word solo also applies to ice climbs and routes done ropeless in the Alps and Greater Ranges. Soloing can also mean going alone with a rope, but free soloing means no rope.

The practice of free soloing has “struck awe in onlookers around the world, with climbers like Alex Honnold daring to scale insane heights,” according to Extreme Scene.

Video footage shows climbers doing so without safety gear:

“Soloing is only done by a minority; most climbers do not practice this extremely dangerous genre,” the Climbing.com article states.