Widener Library

Widener serves as the centerpiece of the 15.6 million-volume Harvard University Library system, the largest university library system in the world.The 320,000-square-foot (30,000 m2) Beaux-Arts brick building houses 57 miles (92 km) of bookshelves and 3 million volumes.

http://en.wikipedia.org/wiki/Widener_Library