Piz Tomül, Mountain summit in Graubünden, Switzerland

Piz Tomül is a mountain summit in the Lepontine Alps that rises to 2,946 meters (9,665 feet) with steep flanks and a defined peak. The mountain dominates the view from the surrounding Safiental and Valser valley regions.

The summit and the Tomülpass below it lie on the old boundary between the municipalities of Vals and St. Martin. St. Martin, which had only 31 inhabitants, was the last municipality in Switzerland to be connected to the electricity grid before it merged with Vals on 1 January 2015. The eastern flank of Piz Tomül belonged to the former municipality of Safien, now Safiental.

The name Tomül recurs across the mountain's slopes: the Alp Tomül below is a summer pasture used by farmers from Flims, and the Tomülgrat on the far side of the pass also carries the name. The former municipality of St. Martin, which held part of the western ridge, was the last municipality in Switzerland to be electrified.

The ascent is a T4 mountain hike from Tomülpass over the south-east ridge; no path is marked, so route-finding is needed. The summit is also climbed in winter. The mountain lies east of Vals, with its eastern part on the former Safien municipal territory.

The name Tomül recurs on both sides of the pass: the ridge opposite the summit is the Tomülgrat, whose high point reaches 2,747 m, while the Tomüllückli is not a crossing at all but a less fractured spot on the west ridge. That west ridge separates the former municipal areas of Vals and St. Martin.