Hämeenlinna (hăˈmānlĭnˌnä) [key], Swed. Tavastehus, city (1998 pop. 45,555), capital of Southern Finland prov., S Finland. It is a lake port and a manufacturing town with plywood mills, tanneries, spool mills, and rubber works. Built around a 13th-century castle on Lake Vanajavesi, the city was chartered in 1638. The beautiful Aulanko-Karlberg natural park nearby is a tourist center. The composer Jean Sibelius was born in Hämeenlinna.