Austin King, 22, from Winona, Minnesota was last heard from on Sept. 17 from the summit of Eagle Peak, the tallest peak in Yellowstone. He climbed Eagle Peak alone in September to celebrate the end of summer and as a personal accomplishment.

King called his parents and two friends from the peak on Sept. 17, cold in the weather conditions of fog and sleet, but thrilled.

Four days later, on Sept. 21, King missed a boat that had been scheduled to take him back to his RV in Grant Village. Hours after this, search crews from Yellowstone and surrounding areas deployed ground and air resources to start a search for the now-missing man. Crews were able to find King’s camp and personal effects in the upper Howell Creek area on the first day of their search.

Yellowstone authorities officially announced their transition from “rescue” searching to a “recovery” search in a statement on Wednesday, the 2nd of October.

In the public statement, Superintendent Cam Sholly said, “Despite significant search efforts over the past week and a half, we have not been able to locate Austin. Although we will continue to hope for the best, I want to extend my deepest sympathies to Austin’s family, friends and colleagues. I also want to thank the teams from Yellowstone and Grand Teton national parks, and Park and Teton counties, Wyoming, who have all worked tirelessly to find Austin in some of the most difficult and remote terrain in Yellowstone.”

Since his disappearance, more than 100 people, search dog teams, ground teams with spotting scopes, trackers, a drone, and two helicopters have searched more than 3,225 miles by air and ground at elevations ranging from 11,350 to 8,400 feet in search for King.