The Danish Straits connect the Baltic Sea to the North Sea through the Kattegat and Skagerrak. Historically, the Danish Straits were internal waterways of Denmark; however, following territorial losses, Øresund and Fehmarn Belt are now shared with Sweden and Germany, while the Great Belt and the Little Belt have remained Danish territorial waters. The Copenhagen Convention of 1857 made all the Danish Straits open to commercial shipping. The straits have generally been regarded as an international waterway.
Toponymy and geography Five straits are named 'belt' (), the only ones in the world. Several other straits are named 'sound' (Danish, Swedish and German: ). Where an island is situated between a "belt" and a "sound", typically the broader strait is called "belt" and the narrower one is the "sound":
Als: separated from the continent by separated from Fyn by the southern part of the Little Belt, an area referred to in German (but not Danish) as Fehmarn separated from the continent by , also separated from Lolland by (German) / (Low German) / (Danish; former spelling: ) Langeland: separated from Tåsinge Island by (Tåsinge is separated from Fyn by ) separated from Lolland by , the southern part of the Great Belt Lolland: separated from Falster by (Falster is separated from Zealand by Strait and by Møn by Grønsund) separated from Langeland by separated from Fehmarn by , which is the common continuation of Great Belt– and Little Belt separated from Zealand by Smålandsfarvandet Zealand () separated from the Scandinavian peninsula by (Danish) / (Swedish) separated from Fyn by the Great Belt separated from Lolland, Falster and Møn (as well as from smaller islands Bogø and Farø) by Smålandsfarvandet, Storstrømmen Ulvsund and Bøgestrøm.
Crossing the straits During the 20th and 21st centuries the surrounding areas grew in population and cross-border trade developed, particularly as part of the European single market. The European Union Scandinavian–Mediterranean Corridor runs north-south through the Danish straits.
Ferries crossed many of the straits but some of these have been replaced with fixed links to reduce journey times. Most significantly, since 1999 the cities of Hamburg and Copenhagen have been linked without the use of ferries. The fixed links include: 1930 – King Christian X's Bridge in Sønderborg 1935 – "Old" Little Belt Bridge 1937 – Storstrøm Bridge 1960 – Siøsund Bridge 1970 – "New" Little Belt Bridge (1970) 1981 – Alssund Bridge 1998 – Great Belt Bridge 1999 – Øresund Bridge 2032 – expected completion of Fehmarn Belt fixed link
See also Kiel Canal Göta Canal Eider Canal List of islands of Denmark March across the Belts
References Denmark 1:500,000 – official map for download Norwegian dictionary: sund Norwegian dictionary: sundre