Metropolitan: Tokyo 23 wards / Cities with population more than 500,000.
Urban: Cities in Tokyo Metropolitan area (other than 23 wards) / Cities in Saitama, Chiba, Kanagawa, Aichi, Kyoto, Osaka and Hyogo Prefectures except for those designated as underpopulated areas by law.
Suburban: Areas other than Metropolitan or Urban.
The above classifications are a guide suggested by NIAD-QE; each university chooses the classifications for its own campuses.