Altdorf (German for "old village") is the capital of the Swiss canton of Uri. The municipality covers an area of 10.23 km². It is built at a height of 462 m above sea-level, a little above the right bank of the Reuss, not far above the point where this river is joined on the right by the Schächen torrent.
The name is sometimes written as Altdorf UR, to distinguish it from Altdorf SH, a small village in the canton of Schaffhausen.
Of the total population of 8757 (2002), 4524 are male, and 4233 are female. The population density of the community is 856 inhabitants per km². In 1900 the population was 3117, all Roman Catholic and German-speaking.
Altdorf is 55 km from Lucerne by the St Gotthard railway and 28 km from Göschenen. Its port on the Lake of Lucerne, Flüelen, is 2 miles distant. There is a stately parish church, while above the little town is the oldest Capuchin convent in Switzerland (1581).
The same year a new carriage-road was opened from Altdorf through the Schächental and over the Klausen Pass (1,948 m) to the village of Linthal (46 km) and so to Glarus. 2 kilometres from Altdorf by the Klausen road is the village of Bürglen, where by tradition Tell was born; while he is also said to have lost his life, while saving that of a child, in the Schächen torrent that flows past the village. On the left bank of the Reuss, immediately opposite Altdorf, is Attinghausen, where the ruined castle (which belonged to one of the real founders of the Swiss Confederation) now houses the cantonal museum of antiquities.