Björkö is an island in Lake Mälaren, about 30 kilometres west of Stockholm. Its name is sometimes translated as “Birch Island,” but for visitors its wider significance is that it contains Birka, one of the best-known Viking-age archaeological sites in Sweden. The island is not itself a reconstructed Viking town. The remains are archaeological ground within a living landscape, and Birka’s marked paths pass through fields, shoreline and low grassy features rather than a modern street grid.
UNESCO describes Birka as a major mercantile town between about AD 750 and 980, positioned where important waterways met. Together with Hovgården, the royal domain on nearby Adelsö, it illustrates the trading networks of Viking-age northern Europe. The designation covers a connected property across two islands: Birka’s settlement and harbour on Björkö, and the royal landscape at Hovgården. A visit to Björkö therefore offers one part of a wider heritage story, not the whole UNESCO property.