20 Francs Castles of Bellinzona

The three castles of Bellinzona — Castelgrande, Montebello, and Sasso Corbaro — were inscribed as a UNESCO World Heritage Site in 2000, which directly prompted this issue four years later. Swissmint has consistently used the 20-franc commemorative silver series to mark Swiss heritage designations, and Bellinzona's listing was the first time a purely military fortification complex from the Swiss territories received that recognition.

The castles controlled the southern approach through the Alps into the Po Valley, a corridor fought over by the Visconti of Milan and the Old Swiss Confederacy for most of the 15th century.