Vadstena (vädˈstāˌnä) [key], town (1990 pop. 5,527), Östergötland co., S Sweden, on Lake Vättern. The town is a tourist center and a port on the Göta Canal; it has a noted lace-making industry. First mentioned in the early 14th cent., Vadstena is the site of the most important medieval cloisters in Sweden, the Convent of St. Birgitta (Bridget), founded c.1370. The town has many historic buildings, including the original convent and Vadstena castle, built by Gustavus I in 1545.