Düsseldorf is one of the economic centers of Germany and is located along the River Rhine in the densely populated Rhine-Ruhr metropolitan area. The city is famous for its nightlife, carnival, events, shopping and for fashion and trade fairs like the Boot Messe (one of the world's best trade fairs for boats and watersports) and Igedo (world leader in fashion). Every year, more than 4 million people visit the Kirmes fun fair which runs for 9 days in the summer.