Bregenz is an Austrian city at the eastern end of Lake Constance (Bodensee). It is the capital of the state of Vorarlberg. The annual Bregenz Festival is a big event, with opera and music performances on the floating lakeside stage known as the Seebühne and the glass-fronted Festspielhaus. The Baroque St. Martin's Tower is topped with a huge wooden dome. It houses a history museum and offers sweeping views of the city.