the capital prefecture of Japan, located in the 関東 (Kantō) region including several archipelagos on the Pacific Ocean, and the 23 special wards in its central part collectively referred to as simply 東京 (Tōkyō, “Tokyo”, former “Tokyo City”)

maintenance

a capital city / a city, metropolis / Short for 東京都 (Tōkyō-to): the capital prefecture of Tokyo

public order

metropolitan police

the Tokyo Metropolitan Police Department, the police department serving Tokyo Metropolis

maintain, keep

Tokyo (a prefecture, the capital city of Japan, consisting of 23 special wards) / Short for 東京都 (Tōkyō-to) the capital prefecture of Japan

(historical) an eastern capital

(historical) the capital of 東漢 (Tōkan, “Eastern Han”) or 後漢 (Gokan, “Later Han”), corresponds to modern Luoyang / (historical) the capital of 北宋 (Hokusō, “Northern Song”), corresponds to modern Kaifeng