The Tokyo Metro Fukutoshin Line , formally the No. 13 Fukutoshin Line , is a 20.2-kilometer (12.6 mi) subway line operated by Tokyo Metro in west-central Tokyo and Wako, Saitama, Japan. The newest line in the Tokyo subway network, it opened in stages between 1994 and 2008. On average, the Fukutoshin Line carried 362,654 passengers daily in 2017, the lowest of all Tokyo Metro lines and roughly one third of its sister Tokyo Metro Yūrakuchō Line (1,124,478).

The Tokyo Metro Tozai Line is a rapid transit line in Tokyo and Chiba Prefecture, Japan, owned and operated by Tokyo Metro. Its name translates to "East-West Line". The line runs between Nakano in Nakano-ku, Tokyo and Nishi-Funabashi in Funabashi, Chiba Prefecture. The Tōzai Line was referred to as Line 5 during the planning stages; the seldom-used official name is Line 5 Tōzai Line . The line carries an average of 1,642,378 passengers daily (2017), making it the busiest line on the Tokyo Metro network. On maps, diagrams and signboards, the Tōzai Line is shown using the color "sky blue" and its stations are given numbers using the letter "T".