The busiest ferry in the United States is the Staten Island Ferry, which annually carries over 19 million passengers on the 5.2 mile (8.4 km) run between St. George Ferry Terminal and South Ferry. Service is provided 24 hours a day, 365 days a year, and takes approximately 25 minutes each way. Each day eight boats transport almost 65,000 passengers during 104 boat trips. Over 33,000 trips are made annually. The Ferry has remained free of charge since 1997. Vehicles have not been allowed on the Ferry since the September 11, 2001 terrorist attacks, though bicycles are permitted on the lower level at no cost. The ferry ride is a favorite of tourists as it provides excellent views of the Lower Manhattan skyline and the Statue of Liberty.