Once the site of a rock quarry, is now a 249-acre park consisting of a variety of habitats; most notably a relatively intact hardwood hammock and mangrove forest.  The hammock at Greynolds is one of the last well-protected natural areas of northern Miami-Dade County.

Tequesta Indians used the Oleta River, which runs along the east side of the park, as a source of transportation.  In the years following, the Seminole Indians used the land along side the river as a trading post and a source of supplies for early Miami-Dade County settlers. The park is named after A.O. Greynolds, the head of Ojus Rock Company, who deeded the land over to Miami-Dade County Parks Department in 1936.