Also, the entire North Shore Long Island is called Gold Coast because that is where the rich and famous of the time used to have summer houses. Many of those were donated to the state to pay off taxes over time. Most towns around that area have a few of those.

Once spring arrives, probably my favorite is Planting Fields Arboretum / Coe Hall. Here is a small video I made there 2 years ago:

http://www.youtube.com/watch?v=gR3_X5P6fLg

You can click on the videos linked on the sidebar to see the manor house itself etc.