Fort Lauderdale is adjacent to the Atlantic Ocean and is known as the Venice of America due to its extensive network of canals. A popular spot for fishing and yachting it is also metropolitan with a diverse culture.  The economy relies heavily on tourism but is also a major manufacturing and maintenance center for yachts. The city is served by Port Everglades the nations second busiest cruise port.  Buses and a commuter rail system connect the major cities and airports in south Florida. The airports in the area are Fort Lauderdale/Hollywood International Airport, Miami International, Palm Beach International and Fort Lauderdale Executive Airport. Fort Lauderdale has six colleges and universities and Broward General Medical Center, which serve as a major training center for medical students.