The Decennovium is strangely confounded by Cluverius (tom. ii. p. 1007) with the River Ufens. It was in truth a canal of nineteen miles, from Forum Appii to Terracina, on which Horace embarked in the night. The Decennovium, which is mentioned by Lucan, Dion Cassius, and Cassiodorus, has been sufficiently ruined, restored, and obliterated, (D'Anville, Anayse de l'Italie, p. 185, etc.)