The Tokyo Metro (東京メトロ, Tōkyō Metoro) is a major rapid transit system in Tokyo, Japan, operated by Tokyo Metro Co., Ltd. (東京地下鉄株式会社, Tōkyō Chikatetsu Kabushiki-gaisha). While it is not the only rapid transit system operating in Tokyo, it has the higher ridership among the two subway operators: in 2014, the Tokyo Metro had an average daily ridership of 6.84 million passengers, while the other system, the Toei Subway, had 2.85 million average daily rides. The company replaced the Teito Rapid Transit Authority (帝都高速度交通営団, Teito Kōsokudo Kōtsū Eidan), commonly known as Eidan or TRTA, on April 1, 2004.

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