The Miami Rock Ridge is an oolitic, continuous outcrop of limestone, part of the Miami Formation, which formerly encompassed a large extent of southernmost South Florida; as part of an ecosystem it formed portions of the Everglades. The traditional base of the elevation, which rises 7 to 8.6 m (23 to 28 ft) above sea level, ranges from northern Miami-Dade County—the approximate latitude of North Miami Beach—southward to the upper Florida Keys and extends southwestward into Everglades National Park, creating a karst-dominated landscape.^[1] A series of tidal channels, dubbed transverse glades, formed within valleys in the ridge and served as conduits for freshwater from the Everglades, thereby modulating the estuarine environment of Biscayne Bay.^[2] One of these glades enclosed the Miami River, a section of whose course featured a 6-foot-2.5-inch (1.892 m) waterfall and 450-foot-long (140 m) rapids until 1908, when it was progressively bypassed by the Miami Canal and partly dredged.^[3][4] Being one of the few areas sited above pre-drainage sea level, the Miami Rock Ridge was heavily exploited for agriculture and real estate.^[5][6]

The coastal ridge was traditionally a component of the endangered pine rocklands, which grew upon the length of the ridge.^[7] The environmental community consisted of a large and continuous expanse of South Florida slash pines (Pinus elliottii var. densa), which was interspersed by tropical hardwood hammocks.^[8] The globally imperiled pine rockland community, which also encompassed the Florida Keys and The Bahamas, supported numerous endemic plant species; 20 percent occur nowhere else in the world.^[7] The communities of the Miami Rock Ridge are maintained by wildfires, including natural fires caused by lightning strikes; this affects the vegetation and its associated inhabitants, thus maintaining a diverse ecosystem.^[9][10] The substrate—often consisting of marl—and climate also affects the height of vegetation; thus a mature subtropical hammock typically does not exceed 59 feet (18 m) on the Miami Rock Ridge.^[11][12] Today the original communities have been largely removed by development, and the remaining pieces of the ecosystems are scattered into tiny fragments in extreme southeast Florida; they now encompass small fractions of their original range.^[7] Simpson Park Hammock and Alice Wainwright Park contain small fragments of tropical hardwood hammock.

• Miami Rock Ridge at Alice Wainwright Park
• View of Biscayne Bay and Key Biscayne from atop the ridge
• General view of ridge from below

• Arch Creek, Florida – Site of a natural arch in the Miami Rock Ridge