Loire (Lwar; anc. Liger), the longest river in France, has its source in the Cevennes, in the dep. of Ardeche, at an elevation of 4511 feet, flows north and north-west through the centre of France as far as Orleans, where it bends round to the south-west and continues on to Tours; thence it follows, in general, a western course to its embouchure in the Bay of Biscay. It is tidal to Nantes, 35 miles from its mouth. Entire length, 620 miles. It becomes navigable a little above Roanne, 550 miles from the sea. At one time the depth of water at its mouth was 19 1/2 feet at ebb-tide ; now it is only 6 1/2 feet. This is due to the vast quantity of sedimentary matter brought down by the river. To the same cause are due the numerous islands that obstruct its lower course and the sandbanks that lie athwart its mouth. The Loire is notorious for the destructive inundations it causes, although the lower part of its course is protected by large dykes or levees, 20 feet high. The chief tributaries are the Nievre and the Maine (which is formed by the Sarthe, its affluent the Loir, and the Mayenne) on the right; and the Allier, Cher, Indre, and Vienne on the left. See The Seine and the Imre, with sixty-one illustrations by Turner (new ed. 1886).
Loire, a dep. of SE. France, formerly part of the province of Lyonnais and the county of Forez. The arrondissements are Montbrison, Roanne, and St Etienne (the capital). Area, 1838 sq. m. ; pop. (1872) 550,611 ; (1901) 644,532.
Loire, Haute, a dep. of central France, formed out of Languedoc, Auvergne, and Forez. The Loire crosses it northwards, the Allier northwestwards. Area, 1915 sq. m. ; pop. (1872) 308,732 ; (1901) 306,671. The arrondissements are Le Puy (the capital), Yssingeaux, and Brioude.