Öland, island and landskap (province) in the Baltic Sea, län (county) of Kalmar, Sweden. It is connected to Kalmar on the Swedish mainland by a road bridge across Kalmar Sound. It is the largest Swedish island after Gotland. Administratively, Öland, together with the surrounding islets, forms the smallest of Sweden’s traditional provinces. Its periphery of limestone and sand ridges encloses an almost barren tract of land. There are a few small streams and one lake, Hornsjön.
On the narrow, alluvial coastland, sugar beets, rye, and potatoes are grown, and there is some cattle raising. Local industries include quarrying, cement making, and sugar refining.
Beginning in 775, Öland frequently played a role in Scandinavian history, especially as a battleground in the wars between Denmark and Sweden. The island’s only large town, Borgholm, contains the ruins of one of the finest castles and strongest fortresses in Sweden, dating from the 13th century or before.