Take a day trip from Miami to Key West, the southernmost city in the United States, without renting a car or having to drive. In about 4 hours, pass more than 42 bridges, including the Seven Mile Bridge, and 34 islands, as you traverse the Overseas Highway. In Key West, enjoy six hours of free time. Explore the quiet city at your own pace or book an optional tour and head out for a ride on the water.