Alaska is not divided into counties, as most of the other U.S. states, but it is divided into boroughs. Many of the more densely populated parts of the state are part of Alaska's 16 boroughs, which function somewhat similarly to counties in other states. However, unlike county-equivalents in the other 49 states, the boroughs do not cover the entire land area of the state. The area not part of any borough is referred to as the Unorganized Borough.

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