volcanic island, northernmost of the central Azores, east-central Atlantic Ocean. The 23-square-mile (60-square-kilometre) island reaches a height of 1,338 feet (408 m) at the summit of Enxôfre Caldera, a volcanic crater. Dense vegetation is supported by the volcanic soils, and wine grapes, fruit, cereals, and cattle are raised. They are marketed through the principal settlements, Santa Cruz (north) and Praia. Discovered in 1451, the island may have been named Graciosa because it is less mountainous than other islands in the vicinity. Graciosa Cave is a well-known cavern, with volcanic formations. Pop. (1991) 5,190.