Saint Helena is in the south Atlantic Ocean, about 1930 km (about 1200 mi) west of Africa. It is of volcanic origin, and its surface is rugged and mountainous, reaching an altitude of about 823 m (about 2700 ft) in the High Hills in the southwest. The climate is moderate and healthful, and the mean annual temperature is somewhat over 21° C (over 70° F). Potatoes and flax are the chief products. The dependency is administered by a governor. The capital and chief port is Jamestown (population, 1987 estimate, 1400). Saint Helena was discovered in 1502 by a Portuguese navigator, João de Nova; it was then uninhabited. In 1659 the English East India Company founded the first permanent settlement. The island was (1815-21) the place of exile of Napoleon, who died there in 1821, in the farmhouse of Longwood, near Jamestown. Area, 122 sq km (47 sq m).