Codanus
The Kattegat (Danish: [ˈkadəɡad]; Swedish: Kattegatt, pronounced [²katːɛɡatː]) is a 30,000 km2 (12,000 sq mi) sea area bounded by the Jutlandic peninsula in the west, the Danish straits islands of Denmark to the south and the provinces of Västergötland, Scania, Halland and Bohuslän in Sweden in the east. The Baltic Sea drains into the Kattegat through the Danish Straits. The sea area is a continuation of the Skagerrak and may be seen as a bay of the Baltic Sea or the North Sea or, as in traditional Scandinavian usage, neither of these.
The Kattegat is a rather shallow sea and can be very difficult and dangerous to navigate, due to the many sandy and stony reefs and tricky currents that often shift. In modern times, artificial seabed channels have been dug, many reefs have been dredged by either sand pumping or stone fishing, and a well-developed light signaling network has been installed, to safeguard the very heavy international traffic of this small sea.
There are several large cities and major ports in the Kattegat, including Gothenburg, Aarhus, Aalborg, Halmstad and Frederikshavn, mentioned by descending size and importance.
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