CONCORD, N.H. (AP) – Eagle Scout Scott Mason kept his cool as overnight temperatures dropped around New Hampshire’s Mount Washington, building a rock cave to protect himself from the mountain’s notorious winds after being stranded in the wilderness.

The 17-year-old from Halifax, Mass., was found Tuesday, after rising water and deep snow stranded him for three nights. He was discharged Wednesday from a hospital after being treated for a painful leg.

Fish and Game Lt. Douglas Gralenski said Mason hunkered down Saturday and Sunday nights below treeline in a bivvy bag – a waterproof sleeping bag shell that can be used as an emergency sleeping bag. Mason built fires each morning.

Gralenski said the teen built a small cave from rocks Monday night to protect himself from the wind.