The Miami River is a river in the U.S. state of Florida that drains out of the Everglades and runs through the city of Miami, including Downtown. The 5.5-mile long river flows from the terminus of the Miami Canal at Miami International Airport to Biscayne Bay. It was originally a natural river inhabited at its mouth by the Tequesta Native Americans, but it was d…The Miami River is a river in the U.S. state of Florida that drains out of the Everglades and runs through the city of Miami, including Downtown. The 5.5-mile long river flows from the terminus of the Miami Canal at Miami International Airport to Biscayne Bay. It was originally a natural river inhabited at its mouth by the Tequesta Native Americans, but it was dredged and is now polluted throughout its route through Miami-Dade County. The mouth of the river is home to the Port of Miami and many other businesses whose pressure to maintain it has helped to improve the river's condition.