Utsuro-bune (虚舟, hollow boat), also Utsuro-fune and Urobune, was an unknown object that allegedly washed ashore in 1803 in Hitachi province) on the eastern coast of Japan). Utsuro means "hollow" and -bune (from fune) means "boat". Accounts of the incident appear in four texts: Oushuku Zakki (1815), Toen Shōsetsu (1825), Hyōryū Kishū (1835) and Ume-no-chiri (1844).
