chain of 14 islands in the Philippines, about 190 miles (310 km) north of Luzon in the Luzon Strait. The Bashi (north) and Balintang (south) channels separate the group from Taiwan and the Babuyan Islands.

Volcanic in origin, the islands are rugged and rocky, but relatively flat and windswept. Only the four largest (Itbayat, Batan, Sabtang, and Ibuhos) are inhabited. The frequency of destructive typhoons dictates both agricultural and architectural patterns. Root crops, particularly sweet potatoes, are the main food crop, and the surplus supports a small livestock industry. Fishing is a supplementary activity. Houses are built of stone and tile in the shelter of swales or trees.

The inhabitants are Roman Catholic and speak Ivatan, a local dialect. Population increase since 1900 has been relatively slow, since many islanders have migrated to the kinder environment of Luzon. The town of Basco, on northwestern Batan Island, is the only national port; it is served by an airfield. Area 81 square miles (209 square km). Pop. (2000) 16,467.