Numerous mokkan (narrow strips of wood on which an official message were written) have been excavated at Den Asuka Itabukimiya Ato (the supposed ruins of Asuka-Itabuki-no-miya Palace), and within these is written a 'kanotomi year' which is equivalent to the 10th year of the reign of Emperor Tenmu (681).
伝飛鳥板蓋宮址から多数の木簡が出土し、それらの木簡の中に「辛巳年」という「天武十年」に相当する年紀が書かれていた。