Hartshorne Woods Park (pronounced: hearts horn) is a 736-acre (298 ha) county park located in Northern Monmouth County, New Jersey, United States, in New Jersey's Bayshore Region. The park has 16 miles (26 km) of trails, several old military bunkers and a small beach with a fishing pier. It is roughly bordered to the north and west by Navesink Ave and Route 36. Its southern borders are Hartshorne Road and the Navesink River. Its eastern border is the Upper Shrewsbury River. The Park is split into three sections from west to east: The Buttermilk Valley Section, the Monmouth Hills Section and the Rocky Point Section.