Inn

The Inn is a river in Switzerland, Austria and Germany. It is a right tributary of the Danube and is 518 kilometres long. The highest point of its drainage basin is the summit of Piz Bernina, at 4,049 metres . The Engadine, the valley of the En, is the only Swiss valley whose waters end up in the Black Sea .

The name Inn is derived from the old Celtic words en and enios, meaning water. In a document of 1338, the river was named Wasser . The first written mention from the years 105 to 109 reads: "... Sextilius Felix... ad occupandam ripam Aeni fluminis, quod Raetos Noricosque interfluit, missus..." The river is also mentioned by other authors of the Roman Empire as Ainos or Aenus . In medieval Latin it was written as Enus or Oenus. The change in the old Bavarian language from e to i turned Enus to In. Until the 17th century, it was written like this or Yn, but also Ihn or Yhn. The double-n appeared only in the 16th century, for example in the Tyrolian Landreim of 1557, and since the 18th century this spelling and pronunciation with a short vowel has been customary.

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