The Incunabula Collection contains most, around 260, of the Helsinki University Library's ca. 420 incunabula (i.e. books printed before year 1501). The collection has been divided into three different sections (Ink. collection, Ink. k. collection and the Ink. F collection of folio sized books). Around one third of the library's incunabula are included in the A. E. Nordenskiöld Collection. Individual incunabula have also been placed in the library's other collections. Additionally, many printed religious books used in Finland during the Catholic era have been placed in the Manuscript Collection. The Incunabula Collection also includes around 20 post-incunabula, printed in the beginning of 16th century.