Castle Clinton National Monument was originally a fort to keep out a British invasion in 1812. Over the years, the Castle has been transformed to welcome theater goers, immigrants, sightseers, and now millions of visitors to New York Harbor as the starting point for visitors to Statue of Liberty and Ellis Island.
I am a National Park freak but I found this spot to be a little ho hum. It is an old fort and the history in the tiny museum is interesting but there isn't much else to it. I am glad its protected but I am not certain it deserves National Park status. If you are in the area, pay it a quick visit, but certainly don't make a special trip just to see it. You will be pretty dissapointed.