Bald Mountain, Mountain peak in Ketchum, United States.

Bald Mountain is a summit in the Ketchum area that rises above 2,700 meters and offers more than 70 different ski runs across the terrain. The slopes feature steep, intermediate, and gentle descents that suit different skill levels and preferences.

Bald Mountain opened for lift-served skiing in Sun Valley's fourth season, 1939–40, with three single-seat chairlifts that unloaded at 9,020 feet (2,749 m), just below the 9,121-foot summit. The lifts gave the resort its main mountain and made the long northeast-face runs reachable by chair.

Bald Mountain is the main ski hill of Sun Valley, opened for lift-served skiing in the resort's fourth season, 1939–40. Its name distinguishes it from the separate Bald Mountain Ski Area near Pierce, Idaho. The slope ratings are relative: much of the 'easiest' terrain would be intermediate at other areas, as beginner runs are on Dollar Mountain.

The peak is accessible from two base areas connected by chairlifts that operate during daylight hours in the winter season. It helps to arrive early and watch the weather, since conditions can affect lift operations and visibility.

Bald Mountain is not the Bald Mountain Ski Area near Pierce in Clearwater County; the two are separate places. In the NBC miniseries 10.5: Apocalypse, the peak is depicted as an extinct volcano that erupts and buries Sun Valley, Ketchum and Hailey in hot gas and ash.