Gap (anc. Vapincum), a town of France, capital of the department of llautes-Alps, 47 m. S. E. of Grenoble, at the confluence of the Bonne and the Luye, affluents of the Durance; pop. in 1866, 8,219. It is situated in a valley shut in by mountains, on which the vine flourishes to the height of 2,000 ft., and is of great strategical importance. It is badly built, but contains a handsome Gothic cathedral. It has been much improved within the present century, and among the new public works are an extensive aqueduct and reservoir. It trades in grain, fruits, cattle, leather, and wool, and has manufactures of linen, silk, and woollen. The town is of Celtic origin, and was at first called Vap. It became a bishop's see in the 5th century. In the 10th century the bishops received the title of prince, of which they were deprived by Francis I.