Miami Rock Ridge

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.

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. 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. Being one of the few areas sited above pre-drainage sea level, the Miami Rock Ridge was heavily exploited for agriculture and real estate.