Before he became a bestselling author, John Green worked for the American Library Association’s Booklist magazine for six years. Now, the novelist and Mental Floss YouTube host is returning to the stacks once more, delivering bibliophiles over two dozen trivia bits about the free repositories of knowledge.

Since Clearchus—the ancient Greek ruler and student of the philosopher Plato—founded the first-known public library around 364 BCE, readers from around the world have rifled through sacred Buddhist manuscripts in Bhutan’s unique temple library; felt equal parts awed and overwhelmed upon entering the Library of Congress; and paid homage to Morocco’s gatekeepers of knowledge by visiting the world’s oldest still-operating library in Fez, which was founded by a woman named Fatima al-Fihri in 859 CE [PDF].

Learn more about these fascinating libraries—along with which famous children’s author was once a librarian, which president was guilty of having a library book that was 221 years overdue, which Francis Ford Coppola film may never have been made without a school librarian’s petition, and more—by watching the video above, or by subscribing to our YouTube channel.