For those who do not know its history, the Statue of Liberty, which stands on the middle of it, was a gift from France in 1884.
Originally the island was called Bedloe's island until 1956 when it was renamed Liberty Island. The State of New York owns it and is responsible for its upkeep. If you never went into the Statue of Liberty, you need to. There are stairs to climb, but the view from the top is simply inspiring. You can see all of Manhattan and the surrounding land.