STS090-751-047 Greater Miami Area, Florida, USA April 1998 The Everglades of southern Florida is the remainder of a wetland system that once covered more than four million acres (1600000 hectares). It is a landscape of flooded sawgrass prairies with numerous hardwood hammocks (islands of hardwood trees) scattered throughout the region on slightly elevated islands. As the water flows from north to south the Everglades functions as a natural water reclamation and recharge system. The light-colored north-south corridor along the Atlantic Ocean is the greater Miami urban area (from just north of Fort Lauderdale southward almost to Homestead). The two east-west, light-colored linear features that cut through the Everglades are Interstate Highway 75 (also known as Alligator Alley or Everglades Parkway ) and U. S. Highway 41.