Unterwalden, Historic paddle steamer and cultural property in Lucerne, Switzerland.

The Unterwalden is a 62-metre paddle steamer built by Escher Wyss in Zurich, with a first-class salon designed by Filippo Cassina of Milan in Neo-Rococo style, featuring parquet flooring with intricate marquetry and etched glass doors. Its bow decoration is the Swiss cross. The ship is licensed to carry 700 passengers.

The Dampfschiffgesellschaft des Vierwaldstättersees ordered the Unterwalden from Escher Wyss in Zurich in 1899, alongside the Uri. Its steam engine was shown at the 1900 Paris Exposition, the launch followed on 12 November 1901, and it entered service on 18 May 1902. A 1961 rebuild added a retractable wheelhouse, funnel and masts to pass under the Acheregg Bridge; after retirement in 1977 it was saved and reopened in 1985, then restored in 2008–2011 for about 10 million Swiss francs.

The first-class saloon was designed by Filippo Cassina of Milan in Neo-Rococo style, with an inlaid parquet floor and etched glass doors; the bow carries the Swiss cross. The paddle steamer is a class A Swiss cultural property of national significance, the first on Lake Lucerne protected as a whole ship by the canton of Lucerne.

The steamer departs from Lucerne's central dock, which has convenient railway connections and is easy to reach on foot. Visitors should arrive with enough time before departure to board comfortably and explore the vessel.

The steamer has a lowerable chimney system that allows it to pass under the Acheregg Bridge and reach Lake Alpnach. This clever engineering solution lets the vessel extend its journey without having to reverse course.