From the longer Wikipedia page , which lists some of the other holdings.
Yale University's Beinecke Rare Book and Manuscript Library (BRBL) was a 1963 gift of the Beinecke family. The building was designed by Pritzker Prize architect Gordon Bunshaft of the firm of Skidmore, Owings, and Merrill, and is the largest building in the world reserved exclusively for the preservation of rare books and manuscripts. It is located at 121 Wall Street in the center of the Yale campus in New Haven, Connecticut, in Hewitt Quadrangle, which is more commonly referred to as "Beinecke Plaza".
Beinecke Library became the repository for books in the Yale collection printed anywhere before 1601, books printed in Latin America before 1751, books printed in North America before 1821, newspapers and broadsides printed in the United States before 1851, European tracts and pamphlets printed before 1801, and Slavic, East European, Near and Middle Eastern books through to the eighteenth century, as well as special books outside these categories.
Now, the collection spans through to the present day, including such modern works as limited-edition poetry and artists' books. The library also contains thousands of linear feet of archival material, ranging from ancient papyri and medieval manuscripts to the archived personal papers of modern writers.
The library's iconic building closed for major renovation following Yale University’s commencement ceremonies in May 2015. The renovation replaces the building's mechanical systems and expands its research, teaching, storage, and exhibition capabilities, and should be complete in September 2016. A temporary reading room in Yale's Sterling Memorial Library will provide researchers access to the library’s collections during the renovation.
It closed May 2015 for major renovation following Yale University’s commencement ceremonies and reopened in September 2016.
The website is