With all that land, there has got to be a couple of libraries, right? Harvard has some of the world’s most famous university libraries that boast a collection that is the oldest in America. There are 79 libraries, the main and largest one is known as the Widener Memorial Library. It houses about 3.5 million works in over 100 languages and 92 kilometers of shelves across ten levels. Four of the floors are underground because they needed to expand and could not go anywhere but down.