1. The Aso Manuscript Collection (1,047 items)
This impressive collection of historical documents, formerly kept at Aso Shrine, contains a wealth of information relating to the Nanbokucho and Kamakura Periods. Of the 1,047 items of this collection, 34 volumes of 304 letters and 36 manuscripts have been designated as Important Cultural Properties
2. The Hosokawa Manuscript Collection ＜Eisei-Bunko＞ (43,867 items)
This is the largest collection of primary source materials on the administration of the Hosokawa government (Hosokawa Han), ranging from the Nanbokucho Period to the early Meiji Period.
3.The Matsui Manuscript Collection (37,221 items)
Old letters and other documents that belonged to the former lords of Yatsushiro Castle, the Matsui family.