Dunderberg Peak, Mountain summit in Mono County, United States.

Dunderberg Peak is a 3,774-metre mountain on the eastern edge of the Sierra Nevada in Mono County, California. It lies within the Hoover Wilderness and is the highest point in Humboldt-Toiyabe National Forest. Two valleys with several mountain lakes flank it to the south and north, and the ghost town of Dunderberg Mill sits on its northeast slope.

Dunderberg Peak was first named Castle Peak. In 1878 a party of the Wheeler Survey renamed it after the mines on its northerly slope, the workings of Dunderberg Mill on the northeast flank. The survey mapped the Sierra Nevada crest in the same period.

The peak's name comes from the Dunderberg Mill, a silver-mining ghost town on its northeast slope that the Wheeler Survey party saw in 1878. The German-American mining name Dunderberg was transferred from the mines to the mountain, replacing the earlier Castle Peak. The mill site below the summit is what remains of that activity.

The peak can be reached via several hiking trails, with access best from June through October when snow has melted. Visitors should come prepared for demanding terrain and bring proper footwear and navigation tools.

Dunderberg Peak is the highest point in Humboldt-Toiyabe National Forest, and its summit is overtopped only by Excelsior Mountain to the south-southwest. The peak's dominance reaches 5.19 km, meaning no higher ground lies within that radius. On the northeast flank stands the ghost town of Dunderberg Mill, a remnant of the mines that gave the mountain its name.