Expo '85 was a world's fair held in Tsukuba, Ibaraki, Japan (Tsukuba Science City, a planned city focused on technology north of Tokyo) between March 17 and September 16, 1985. The theme of the fair was "Dwellings and Surroundings - Science and Technology for Man at Home". Attendance was over 20 million and 111 countries participated. Worlds Fair is any of various large expositions held since the mid-19th century. ... Tsukuba (Japanese: ã¤ãã°å¸ Tsukuba-shi) is a planned city located in Ibaraki Prefecture, Japan. ... March 17 is the 76th day of the year in the Gregorian Calendar (77th in leap years). ... September 16 is the 259th day of the year (260th in leap years). ... 1985 (MCMLXXXV) was a common year starting on Tuesday of the Gregorian calendar. ...