Roosevelt Island

For most of its history, this narrow island in the East River was where New York sent the people it didn’t want to see. Called Blackwell’s Island, and later Welfare Island, it held a prison, a workhouse, a smallpox hospital and a huge lunatic asylum. The actress Mae West was sent to its jail in 1927 for starring in a play called Sex. In the 1970s, the old institutions were cleared away and the island was reborn as Roosevelt Island, a planned community of apartments, parks and almost no cars. Start with a ride on the tram, then walk from the ruins at the southern tip to the lighthouse at the north.