Since the Edo era, Mitarai prospered as the port town for the world wide trader's ships to wait for the favorable wind and tide. There have been still protected and listed buildings left from the early Edo to Showa era designated as an important cultural buildings. Also Osakishimojima had been known as an old key junction of salt trade and courtesans 'Oiran' in licensed quarter until the Showa 30's (50's).