I've been a fan of the Strand for years. I've always thought of it as the quintessential NY experience. It's located in Union Square (a few blocks away from a behemoth Barnes & Noble) but the Strand does its fair share of business.
First and foremost, they always have discounts on all books and not just the most recent best sellers (try buying Catcher in the Rye at a discount at B&N).
There is a great selection of old, new and obscure books and they have a great New York section. I also enjoy the childrens' book section downstairs. Plus, you can get reviewers' books of best-sellers for half off! A steal!
The downside? You have to check in your bag at the front door. Blah. I hate doing this. There's no air-conditioning (they recently renovated the store and added a/c but believe me, it feels like there's nothing there) so the store can get incredibly hot and uncomfortable (definitely not the B&N experience). Also, sometimes the staff is too busy entertaining their hip selves and ignore you or act surly. So if you can deal with all of that, then it's worth the trip for a great book at a good price.
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