Few people—New Yorkers or tourists—ever get around to exploring Staten Island , but nearly everyone rides the Staten Island ferry (southern tip of Manhattan, 718/727-2508, www.siferry.com , daily, 24 hours a day, every 15–30 minutes, free), one of the best deals in the city. The views of Manhattan  from the harbor are spectacular, especially at twilight when the sunset reflects off a hundred thousand windows, or at night, when the skyline lights up like a carnival midway.
On your right, as you head toward Staten Island, are Ellis Island and the Statue of Liberty . On your left are Governors Island and the Verrazano-Narrows Bridge. Governors Island, where 1,500 Confederate soldiers were imprisoned during the Civil War, became a U.S. Coast Guard Station in 1966. The Coast Guard left in 1998 and the federal government sold it to the city of New York for $1 in 2002. Governors Island is now open to the public weekends through the summer and is accessed by a free ferry.
From Manhattan ferries leave from the Battery Maritime Building at 10 South Street. Ferries leaving from Brooklyn  leave from Fulton Ferry Landing, at the end of Old Fulton Street.
The Staten Island ferries leave every 15 minutes during rush hour, every half hour during much of the day, and every hour at night.