Minato-ku = ward of Tokyo, home to Shinagawa, Azabu, Roppongi, etcpic.twitter.com/YHgPZC48hD
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Whereas "Greater Tokyo" refers to Tokyo Metropolis + several adjacent prefectures
Not perfect comparison w Boston but basically: 23 Wards = City of Boston Tokyo Metropolis = Suffolk County Greater Tokyo = Greater Boston
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