Vatican Apostolic Library (Vatican City)

Founded in 1475, the Vatican Apostolic Library safeguards 80,000 manuscripts and 1.6 million printed books spanning two millennia, with a digitization initiative that has made 25,000 manuscripts online, including the oldest complete Bible. Outpacing Trinity College Library (#7) in manuscript holdings by 400 times, it also houses 8,600 incunabula from before 1501. Access remains restricted to 4,000 scholars per year, preserving treasures while its online presence reaches millions globally, setting a benchmark for rare manuscript preservation.