Allenhurst is a Borough in Monmouth County. Its population at the 2010 census was 496. The borough is within close proximity to New York City and is a stop on the New Jersey Transit North Jersey Coast Line.
The borough has a total area of 0.3 square miles, of which 0.3 square miles is land and 0.04 square miles (7.14%) is water.
A number of historic structures are present in Allenhurst, in Victorian, Queen Anne, Italian Renaissance Revival, Tudor Revival, Prairie, Mission Revival, American Craftsman, Shingle, Colonial Revival, Neoclassical and Gothic Revival architectural styles. These buildings are protected by law.
The Allenhurst Beach Club, a 2,450 member recreational facility, has been popular for generations. It features a large salt water swimming pool, a children's wading pool, cabanas and bathhouses.