Évvoia (ĕvˈēä) [key] or Euboea yōbēˈə, island (1991 pop. 205,502), 1,467 sq mi (3,800 sq km), SE Greece, separated from Boeotia and Attica on the Greek mainland by the Évripos strait. Khalkís is the main city and the administrative center. Évvoia is the largest of the Greek islands after Crete. The island is generally mountainous with fertile valleys; the highest points are Mt. Delphi (c.5,725 ft/1,745 m) and Mt. Oche (c.4,590 ft/1,400 m). Sheep, goats, and cattle are raised, and olives, grapes, and wheat are grown. Magnesite and lignite are mined, and marble is quarried. The island was settled by Ionian and Thracian colonists and was divided among seven independent cities, of which Khalkís and Eretria were the most important. Powerful and prosperous by the 8th cent. B.C., these cities established colonies in Macedonia, S Italy, and Sicily. The island was under the hegemony of Athens from 506 to 411 B.C. and was taken (c.338 B.C.) by Philip II of Macedon. It was annexed by Rome in 194 B.C. and later passed under Byzantine rule. As a result of the Fourth Crusade, it became (early 13th cent.) a colony of Venice. It was ceded to the Ottoman Turks in 1470. The island rebelled against the Turks in 1821 and in 1830 was incorporated into Greece. Its name in the Middle Ages was Negropont [black bridge], for the bridge connecting Khalkís with the mainland.