Martynas Mažvydas National Library of Lithuania (), located in Gediminas Avenue and founded in 1919, is a national cultural institution which collects, organizes and preserves Lithuania's written cultural heritage content, develops the collection of Lithuanian and foreign documents relevant to research, educational and cultural needs of Lithuania, and provides library information services to the public. As of 1 July 2019, its electronic catalog has 1,140,708 bibliographic records.