What is the largest island in the Baltic Sea?

The largest island in the Baltic Sea is Gotland. This Swedish island covers about 2,994 square kilometres and lies roughly 90 kilometres east of mainland Sweden in the central Baltic Sea.

Gotland is both an island and the name of a Swedish county, municipality, historical province and diocese. Its largest town and administrative centre is Visby, a medieval city famous for its exceptionally well-preserved town wall. Visby’s historic centre became a UNESCO World Heritage Site in 1995.

The island’s landscape is shaped by limestone bedrock, producing distinctive sea stacks known as rauks, caves and broad, relatively flat terrain. Gotland has also been important for trade across the Baltic for centuries. Archaeologists have found large Viking Age silver hoards there, reflecting the island’s position along historic commercial routes.

Gotland is sometimes confused with Saaremaa, Estonia’s largest island, which is the Baltic’s second-largest island at about 2,673 square kilometres. Denmark’s Zealand is larger than Gotland, but it sits on the Baltic’s edge in the Danish Straits and is not usually counted as an island fully enclosed by the Baltic Sea. Under the standard geographic definition, Gotland is the accepted answer.