Administrative divisions of the Netherlands
The Netherlands has several levels of administrative subdivisions. The first level of subdivision consists of 12 provinces. The second level of subdivision consists of 345 municipalities. The country is also subdivided into 21 water districts, governed by a water board ("waterschap" or "hoogheemraadschap"), each having authority in matters concerning water management. Direct elections of the water boards take place every four years. Group of provinces. The Group of provinces () is a European subdivision of the Netherlands. It meets the needs of Eurostat, the European statistical institute, which has defined a classification of territorial units for  statistics. These groups correspond to the first European statistical level (NUTS 1). There are four of them: Northern Netherlands, Eastern Netherlands, Western Netherlands and Southern Netherlands. COROP regions. A COROP region is a division of the Netherlands for statistical purposes, used by Statistics Netherlands, among others. The Dutch abbreviation stands for , literally the Coordination Commission Regional Research Programme. These divisions are also used in the EU designation as NUTS 3. Water boards. Typically, a water board's territory is made up of one or more polders or watersheds. The territory of a water board generally covers several municipalities and may  even include areas in two or more provinces. As of 2021, there are 21 water boards in The Netherlands. Municipalities. As of January 2022, there are 345 municipalities (). Municipalities are the second-level administrative division in the Netherlands and are subdivisions of their respective provinces. Their duties are delegated to them by the central government and they are ruled by a municipal council that is elected every four years. Municipal mergers have reduced the total number of municipalities by two-thirds since the first official boundaries were created in the mid 19th century. Municipalities themselves are informally subdivided into districts  and neighbourhoods for administrative and statistical purposes. These municipalities come in a wide range of sizes, Westervoort is the smallest with a land area of and Súdwest-Fryslân the largest with a land area of . Schiermonnikoog is both the least populated and the least densely populated municipality at . Amsterdam has the highest population with 872,757 residents, whereas The Hague is the most densely populated with a density of .