The "zero point" road marker in the middle of Nihonbashi Bridge. This marks Nihonbashi as the starting point for Japan's national highway network even today.
Nihonbashi‘s development, evolution, and success are tied to its roads: the five major roads that began in Nihonbashi, waterways that were essential for trade, and the network of alleys within the chonin-machi residential and commercial neighborhoods that first clustered around Edo Castle.
"Nihonbashi After the Snow" (Nihonbashi Yukibare), by Hiroshige Ando. Part of the "One Hundred Famous Views of Edo" (Meisho Edo Hyakkei) Collection, courtesy of the National Diet Library.
In 1604, the Edo Period shogunate designated the Tokaido Road, Koshukaido Road, Oshukaido Road, Nikkokaido Road, and Nakasendo Road as the "five Gokaido roads," Japan's main avenues of transportation and trade. Nihonbashi marked the starting point for this major road network. A surviving passage from "Notes on the Lord's City" (Gofunai Biko), a paper from the Edo Period shogunate, states: "This bridge shall be the center of Edo, travel to other countries shall begin here, and its name shall be Nihonbashi."
As the center of so much travel and commerce, Nihonbashi quickly flourished. More than anywhere else in the country, Nihonbashi was a center for trade, development, and cultural exchange.
With a population of more than 1 million people by the mid-18th century, Tokyo relied on rivers and canals to bring in vital supplies. City planning was key in allowing Tokyo to not only sustain itself, but grow: the city created waterways that connected the rivers to the ocean, extended the waterways inland, and built canals and riverbanks in ocean-facing commercial districts. These innovations allowed Tokyo to quickly and efficiently take in goods delivered by sea from throughout Japan.
In particular, the waterside commercial districts along the Nihonbashi River, Kyobashi River, Sanjukenbori, and Hachobori were considered the main arteries of water transport, vital to sustaining life in Tokyo.