Inland Rivers
The U.S. inland waterway system is comprised mainly of the Mississippi River and its tributaries and the Gulf Intracoastal Waterway (see map above) and is one of the busiest, cost-efficient, productive and safest transportation systems in the world. The inland waterway system comprises 12,000 miles of navigable interconnected rivers, canals and intracoastal waterways serving the U.S. as water highways.