Sterling Memorial Library (SML) is the main library building of the Yale University Library system in New Haven, Connecticut, United States. Opened in 1931, the library was designed by James Gamble Rogers as the centerpiece of Yale's Gothic Revival campus. The library's tower has sixteen levels of bookstacks containing over 4 million volumes. Several special collections—including the university's Manuscripts & Archives—are also housed in the building. It connects via tunnel to the underground Bass Library, which holds an additional 150,000 volumes.