The Kiel Canal or Nord-Ostee-Kanal (North Sea Baltic Canal) as it is known in German, is the shortest link between the North Sea and the Baltic. The original Canal, the Eider Canal, was built in 1784, but was eventually deemed too shallow to accommodate the increasing number of larger vessels. The Kiel Canal was completed in 1895 at a cost of 157 million marks, and has been progressively widened over the years. It is now 97km/53.2 nautical miles long, 12 metres deep and 164 metres wide. The Kiel Canal is also the busiest manmade waterway in the world. Over 60,000 ships pass through every year, as well as around 25,000 private yachts during the summer. It therefore comes as no surprise that the canal is very precisely organised to ensure a faultless flow of traffic. The Kiel Canal (Nord-Ostee Kanal) (formerly Kaiser Wilhelm Canal) connects the Baltic with the North Sea. Built by Germany in the years (1895) before World War I, the canal allowed the German Navy to move from Baltic Bases to the open sea without traveling through international waters. Entering the Brunsbuttel Lock The canal connects the river Elbe at Brunsbuettel with the Baltic Sea at Kiel. Both entrances in Brunsbuettel and Kiel-Holtenau are equipped with four locks. The Locks are 305 metres in length and 46 metres wide. It takes between 7 and 9 hours to transit the Canal, but this saves sailing about 250 nautical miles through the often difficult waters of the Skagerrak. The canal permits passage of vessels with a maximum draught of 9.5m and the size limitations are 160m length and 27m width, or 193m length and 20m width. Vessels that are longer or wider can use the waterway only if their draught is lower; the maximum length is 235m and 23.5m width, but draught may not exceed 7m. The waterway operates a two way traffic system. Two traffic control stations monitor and collect data on ships' movements, co-ordinating a flow of information from visual observations made at locks and 'sidings' along the canal's length. (Sidings are specially widened parts of the Kiel Canal). Rollers optimise the traffic flow by using the sidings to organise priorities. In the Brunsbuttel Lock According to a classification by the canal authority Wasserund Schiffahrtsdirektion Nord (WSD), all ships are placed into one of six groups based on length, width, draught and cargo characteristics for example dangerous cargoes. These groups determine the traffic on the canal. For example, group six contains the largest ships that may transit. Vessels whose added group figures exceed six (for example one group 'three' and one group 'four' ship), may only meet at the sidings. Overtaking is only permitted if the total of the two ships' groups numbers is not higher than five. On the western part of the-canal between Brunsbuettel and Ruesterbergen, vessels with a maximum group figure of eight can meet on the waterway as a result of the widening project in this segment from the original 110m to 160m at the surface. However, in the eastern part of the canal the geography is such that it does not allow for widening. WSD expanded its traffic surveillance and control in 1997. For the first time ever, one of the 12 sidings was automated and is now supervised via remote control from the station at Kiel-Holtenau. A computer assisted traffic control system, Verkehrissicherungssytem (VSS), is also in use. VSS involves constant radio locating of the vessels through the use of the transponders which are put onboard a ship upon her entry into the canal. The transponder will then constantly store the vessel's technical data, such as position, and transmit this to the stations. Maximum speed on the waterway varies. The maximum speed for ships of group six or those with more than 8.5m draught is 12km per hour, for all other ships it is 15km/hr.