TRAZ-OS-MONTES (i.e. across the Mountains), an ancient frontier province in the extreme N.E. of Portugal, bounded on the N. and E. by Spain, S. by the river Douro which separates it from Beira, and W. by the Gerez, Cabreira and Marão Mountains, which separate it from Entre-Minho-e-Douto. Pop. (1900), 427,358; area, 4,163 sq. m. For administrative purposes Traz-os-Montes was divided in 1833 into the districts of Braganza (q.v.) and Villa Real (q.v.). The surface is generally mountainous, although there are tracts of level land in the veigas or cultivated plains of Chaves and Miranda do Douro, and in the cimas or plateau region of Mogadouro. The highest peak is Marão (4642 ft.). The province belongs to the basin of the Douro and is chiefly drained by its tributaries the Tua, Tamega and Sabor. Its inhabitants belong to the old Portuguese stock, and resemble the Spaniards of Galicia in physical type, dialect and character. The Paiz do Vinho (see Oporto) is the chief wine-growing district in Portugal; other products are silk, maize, wheat, rye, hemp, olive oil and honey. There are important mineral springs and baths at Vidago and Pedras Salgadas. The principal towns are Braganza, Chaves and Villa Real.