A 66-year-old woman was rescued from a Boulder County trail Friday after being crushed by a horse, the Boulder County Sheriff’s Office said.

Deputies said the woman was riding a horse on the Coulson Gulch Trail about 11 a.m. when the ground gave way under the horse, causing it to roll over on the woman.

The woman, a resident of West Des Moines, Iowa, suffered life-threatening injuries and could not leave to get help.

Deputies said the Big Elk Fire Department and Estes Park paramedics quickly responded and provided medical care, stabilizing the woman.

The Rocky Mountain Rescue Group then used a wheeled litter to evacuate the woman to an awaiting MedEvac helicopter. MedEvac provided further medical care and flew the woman to a Boulder-area hospital.

The woman survived but her condition is unknown, deputies said.

The rescue lasted approximately three hours.

Other agencies that assisted with the rescue included the Pinewood Springs Fire Protection District, Lyons Fire Protection District and City of Longmont Button Rock Rangers.