Yamanote

One month ago, I wrote about how Edo was divided in two regions, Yamanote (towards the mountain) and Shitamachi (lower city). Yamanote included the area west of Imperial Palace (part of today's Chiyoda, Minato, Shibuya, Meguro, Suginami, Nakano, Shinjuku and Bunkyo), while Shitamachi included the area towards the east.

In 1885, in the Yamanote area started the construction of a train track, connecting Shinagawa and Akabane. In 1903 a different track was built between Ikebukuro and Tabata and the Yamanote line was born in 1909, when these two tracks were connected.
Interesting is that the Yamanote loop was completed in 1925, with a line passing through... Shitamachi, including Kanda and Ueno.