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Hispanic or Latino of any race were 16.76% (971) of the population. There were 3,931 housing units at an average density of 3,761.4 per square mile (1,452.3/km 2).
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The population density was 5,544.0 per square mile (2,140.6/km 2). The 2010 United States census counted 5,794 people, 2,695 households, and 1,267 families in the borough. The borough's name means "beautiful sea" in Italian. The city acquired its current name, Borough of Belmar, on November 20, 1890. On April 16, 1889, it became the City of Elcho borough, which lasted for a few weeks until the name was changed to the City of Belmar Borough on May 14, 1889.
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What is now Belmar was originally incorporated as Ocean Beach borough by an act of the New Jersey Legislature on April 9, 1885, from portions of Wall Township, based on the results of a referendum held two days earlier. As of the 2020 United States census, the borough's population was 5,907, an increase of 113 (+2.0%) from the 2010 census count of 5,794, which in turn reflected a decline of 251 (−4.2%) from the 6,045 counted in the 2000 census. Belmar is a borough situated on the Jersey Shore, within Monmouth County, in the U.S.
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