The Sound (Danish Øresund, Danish pronunciation: [ˈøːɐsɔnˀ], or Swedish Öresund, pronounced [œrəˈsɵnd]), locally known as Sundet, is the strait that separates the Danish island Zealand from the southern Swedish province of Scania. Its width is just 4 kilometres (2.5 mi) at the narrowest point between Kronborg Castle at Elsinore (Helsingør in Danish) in Denmark, and the northern harbour of Helsingborg in Scania, Sweden. The strait has also lent its name to the Øresund Region of 3.8 million inhabitants on both the Danish and Swedish sides.
Øresund is one of the three Danish Straits that connects the Baltic Sea to the Atlantic Ocean via Kattegat, Skagerrak and the North Sea, and is one of the busiest waterways in the world.
The Øresund Bridge (which includes a 3 km tunnel) between Danish capital Copenhagen and the largest city of Scania, Malmö was inaugurated on 1 July 2000 by Queen Margrethe II of Denmark and King Carl XVI Gustaf of Sweden. Ferries run around the clock between Helsingborg, Sweden and Helsingør, Denmark.