The Tokyo Metro is a major rapid transit system in Tokyo, Japan, operated by the Tokyo Metro Cooperation under the Tokyo Metro Co., Ltd. Act. The system opened in 1927 as the Tokyo Underground Railway, becoming the first underground railway in Asia. It is the larger of Tokyo's two subway operators, with an average daily ridership of 6.52 million; the other operator, the Toei Subway, carries approximately 2.85 million passengers per day as of 2023. Tokyo Metro Co., Ltd. is a special company established on April 1, 2004, through the privatization of the Teito Rapid Transit Authority. It is now one of Japan's major private railway operators. Tokyo Metro operates a network comprising 9 distinct subway lines and 11 routes with 180 stations totaling 195.0 km. Eight of these lines were inherited directly from the TRTA, including the historic Ginza Line which was once operated by Tokyo Underground Railway and the Tokyo Rapid Railway. The ninth line, the Fukutoshin Line, opened in 2008 after the launch of the new private company. The company has been a member of the Japan Private Railway Association and it is formally recognized as Japan's 16th major private railway company. Wikipedia