Denmark Region, which encompasses the Copenhagen metropolitan area with the exception of the subtracted province East Zealand but includes the Baltic Sea island of Bornholm, has a population three times larger than that of North Denmark Region, which covers the more sparsely populated area of northern Jutland. Under the county system certain densely populated municipalities, such as Copenhagen Municipality and Frederiksberg, had been given a status equivalent to that of counties, making them first-level administrative divisions. These "sui generis" municipalities were incorporated into the new regions under the 2007 reforms. The Kingdom of Denmark is a unitary state that comprises, in
Denmark or so rivers, and the most significant include the Gudenå, Odense, Skjern, Suså and Vidå—a river that flows along its southern border with Germany. The Kingdom of Denmark includes two overseas territories, both well to the west of Denmark: Greenland, the world's largest island, and the Faroe Islands in the North Atlantic Ocean. These territories are self-governing and form part of the Danish Realm. Denmark has a temperate climate, characterised by mild winters, with mean temperatures in January of , and cool summers, with a mean temperature in August of . The most extreme temperatures recorded in Denmark, since 1874