What is the main difference in neighborhoods between NYU and Columbia University?

Answer 1

They arent completely different, but Columbia is a little less intensely urban.

NYU is right downtown. You walk directly out of your dorm into a city street. The classroom buildings, library, etc are just large city buildings on a city street.

Columbia is a few miles uptown. It is an urban setting, but more of a residential type area with four or five story apt buildings and retail stores, etc around it. The university has a central campus, although it is quite small - but it does have a couple of very small lawns where kids play frisbee sometimes. The dorms are around the periperhery of the campus so you walk out of your dorm into the middle space. It is concrete mostly, but at least it is a university open space. The main library has a big wide set of stone steps and the kids hang out there - they call it the "urban beach."

The only really nice campus in NYC is Fordham U. which is about 2 or 3 miles north of Columbia. They have a lot of green space, trees, and separated building surrounding by grassy areas. It is much more like a suburban campus, but you can still hop a subway and be downtown in a little while.