Piz Ault, Mountain summit in Grisons, Switzerland

Piz Ault is a 3,027-metre summit in the Glarus Alps, south of the Oberalpstock. Three ridges lead to the peak, while a fourth, less distinct ridge runs south. The border between the cantons of Uri and Graubünden follows its eastern and northern ridges, so three-quarters of the mountain lies in Graubünden.

The border between the cantons of Uri and Graubünden runs along Piz Ault's eastern and northern ridges, which makes the mountain three-quarters Graubünden territory. The municipalities of Disentis and Sedrun lie to the south and Silenen to the northeast. The sources record no founding date or medieval event for this boundary line.

The winter sports area on Piz Ault's southwestern face is reached from Disentis in the canton of Graubünden, which lies south of the mountain. A T-bar lift climbs to roughly 200 metres below the summit, so the upper slope is served by lift rather than by foot. No marked path leads to the peak at any season.

A T-bar ski lift provides winter access to within about 200 meters of the peak, while summer ascents lack marked hiking routes. Visitors should consider seasonal conditions and weather, as winter access is more developed than alternatives.

The Uri–Graubünden cantonal border runs along the eastern and northern ridges, so roughly three-quarters of the mountain lies in Graubünden. The municipalities meeting here are Disentis and Sedrun to the south and Silenen to the northeast.