The trading post of Birka on the island of Bjorko in Lake Malaren was established in the eighth century and is thought to be the oldest town in Scandinavia. The founder was the Svea king, who had his royal residence on nearby Adelso. About 100 years later, Birka is described by a writer as having many rich merchants and an abundance of all types of goods and a great deal of money and valuables. It was thought to have has 1,000 inhabitants, including craftsmen of every kind, whose products attracted merchants from distant countries.

The town was planned on uncomplicated lines. People lived in modest houses which stood in rows overlooking the long jetties. At these lay the ships which took the Vikings out on trading missions and war expeditions.

Today, Bjorko is a green island with meadows and juniper-covered slopes. It has a fascinating museum and ongoing archaeological digs. The museum shows how Birka would have looked in its heyday, along with some of the finds.