This is the Strand Bookstore, the biggest used bookstore in the world. According to its website, it has 18 miles of used, new, rare and out-of-print books in its stores. Most of the books here are 50% or more off the listed prices.
Before the arrival of Amazon.com and BarnesAndNoble.com, the Strand Bookstore was the biggest mail order book company in the country. I remember browsing through their catalogues as a young college student in the early 1990s.
So have you read any good books lately? I just finished Eat Pray Love by Elizabeth Gilbert recently, which came highly recommended by a co-wroker.