Which library holds the world's biggest collection of Shakespearean First Folios?

Standard Oil of New York executive Henry Clay Folger, a graduate of Amherst College and Columbia University, was an avid collector of Shakespeareana, beginning in 1889 with the purchase of a 1685 Fourth Folio. Toward the end of World War I, he and his wife Emily Jordan Folger began searching for a location for a Shakespeare library based on their collection. They chose a location adjacent to the Library of Congress in Washington, D.C. The land was then occupied by townhouses, and Folger spent several years buying the separate lots. The site was designated for expansion by the Library of Congress, but in 1928, Congress passed a resolution allowing its use for Folger's project.