New York is this kind of City which does not have any boundaries.
The best way to experience it is to go to Grand Central station , take any train and go for any day trip around.You will maybe no more be in New York but this so unique spirit of liberty will always be there.
Something you have to do absolutely if you like art is going to Dia Beacon.
The trip along the Hudson is very pleasant in any season.
And if you are at least 2 and have to wait for the train in Grand Central, you can play that game which consists in finding the spot under a curve ceiling where the echo allows you whispering or speaking very low agaisnt the wall and your friend can hear you from the opposite side! One clue : it is in a small allee behind the counters and next to an oyster place...
Very oftern, different kind of exhibits and performances take place and you could find yourself in the middle of a cocktail party surrounded by artists and art lovers, what else do you need for a perfect week-end?
Want some examples of art pieces you could find there? Louise Bourgeois, Richard Serra, Joseph Beuys, Max Neuhaus, Sol Lewitt, Robert Irwin and more infos here : http://www.diacenter.org/sites/main/beacon