Once there was a library of Nalanda University in India. It was one of the biggest libraries in the world. It contained many sacred texts, information about Vedas, Ayurvedic Treatments, and many religious texts of Hindu Religion; But alas, it was set on fire and burnt down by a Mughal named Bakhtiyar Khilji in 1193. 9 million books were burnt down due to the incident. You could imagine how big the library was because it was continuously being burnt down for 3 months