The Kiel Canal used also to be known as the Kaiser Wilhelm Canal and is the busiest sea waterway in the world today. It is considered to be the main trading route in Northern Europe. It connects Scandinavia and the Baltic States to world trade, acting as the gateway to the Baltic Sea. Day and night, more than 37,000 ships a year pass through the canal. The most important port along the canal is Rendsburg. One of the attractions of the Kiel Canal is the railway bridge and the transporter bridge suspended below it in Rendsburg.