Kilometre Zero of Japan's Railways

The marking of the Kilometre Zero is popular in many countries and Japan is no exception. I found two such markers in Japan: one is the KM 0 for the roads, located on the Nihonbashi bridge in Tokyo, the starting place of the Five Routes (Gokaidō) connecting the old Edo to the 5 important provinces.

The second marker, pictured in today's photo, is the KM 0 for the Japanese Railways: located inside the JR Tokyo Station, the marker can be found on the platform number 20-21 (which is for the Tohoku, Yamagata, Akita, Joetsu and Nagano Shinkansen).