Brenner Pass, mountain pass, south central Europe, lowest of the main passes through the Alps, between Innsbruck, Austria, and Bolzano, Italy. Reaching a maximum elevation of 1,371 m (4,497 ft), the pass is part of the shortest overland route between Austria and Italy. Both a highway and a railroad connecting the Austrian and Italian rail systems extend through it. In use since antiquity, Brenner Pass has often figured prominently in the history of south central Europe. The Romans built a road through the pass, and it was the chief invasion route followed by the Germanic tribes that overran Italy in the 5th century. In later times the pass was frequently used by rulers of the Holy Roman Empire.