On October 1st, 2023, Seibu Railway celebrated the 40th anniversary of their Seibu-Yurakucho line. In commemoration, Seibu will operate an anniversary train until March, 2024.
Let me review the Seibu-Yurakucho line to start. It's a connecting line between the Seibu-Ikebukuro line and the Tokyo Metro-Yurakucho line. Connecting Nerima on the Seibu-Ikebukuro line and Kotake-Mukaihara on the Tokyo Metro-Yurakucho line, its route length is 2.6 kilometers. The track is underground and double. There is an intermediate station, Shin-Sakuradai on the line. 8-car or 10-car trains are operated every 5 to 10 minutes. The line name is "Seibu-Yurakucho line", but the route doesn't pass through "Yurakucho" in the central part of Tokyo. Why? Because, the Seibu-Yurakucho line was initially planned as a part of Subway Line 8, namely the Yurakucho line, by Transport Council of the Japanese government in 1970. It's integrated with the Tokyo Metro-Yurakucho line, which passes through "Yurakucho". As you know, the trains on the Seibu-Yurakusho line are currently operated onto the Tokyo Metro-Fukutoshin line as well, so, the situation has changed.
The anniversary train is set 6017 of the EMU Seibu 6000 series. It has yellow-colored special stripes on the bodies. As you know, yellow is the line color of the Tokyo-Metro Yurakucho line; meanwhile, the standard Seibu 6000 series trains have blue-colored stripes. The anniversary train also has a special plate on the front celebrating the 40th anniversary. Congratulations on the 40th anniversary of the Seibu-Yurakucho line! It's the short connecting line, but the great transportation artery in the western part of Tokyo.
Special plate of "the 40th anniversary of the Seibu-Yurakucho line"