Brenner Pass (brĕˈnər) [key], Ital. Brennero, Alpine pass, 4,495 ft (1,370 m) high, connecting Innsbruck, Austria, with Bolzano, Italy. The lowest of the principal Alpine passes, it was an important Roman route through which many invasions of Italy were made. A long carriage road was built c.1772, and the railroad was completed in 1867. The pass became the border between Italy and Austria after World War I. During World War II, Hitler and Mussolini held three meetings there. Today the Brenner Highway, constructed in the early 1970s, is one of the major roads between Austria and Italy.