The village that became the doorHow a hundred houses on a mudflat turned into the place Japan met the world

The Treaty of Amity and Commerce, signed in 1858, named Kanagawa as one of the ports Japan would open to foreign trade. Kanagawa was a busy post town on the Tokaido, the highway between Edo and Kyoto, and that was precisely the problem: the shogunate did not want foreign merchants standing on the road its own lords travelled.

So it built the port two miles away, on a sandspit in front of a fishing village called Yokohama, and declared that this was, for treaty purposes, Kanagawa. The foreign envoys objected in writing. Then the ships came anyway, and on 1 July 1859 the port opened.

A city designed to be a quarantine

The settlement was laid out inside a moat with guarded gates. The area is still called Kannai — "inside the barrier" — and the name is the whole policy in four syllables. Foreigners lived and traded inside; the Japanese town grew outside; a bridge and a checkpoint sat between them.

Within a decade the containment had failed in the most complete way possible. The village of a hundred households became a city. Japan's first railway ran from Shimbashi in Tokyo to Yokohama in 1872. Gas lamps lit Bashamichi the same year. Foreign merchants on the Bluff at Yamate looked down on a harbour handling most of Japan's trade with the outside world.

Kannai means "inside the barrier." The barrier is gone; the street grid it enclosed is still there, and it is still where you walk.

Then it was destroyed. Twice.

On 1 September 1923 the Great Kanto Earthquake struck almost directly beneath the bay. Yokohama, closer to the epicentre than Tokyo, lost the overwhelming majority of its buildings to the shaking and the fires that followed. Around twenty-six thousand people died in this city alone. The treaty port — the brick banks, the trading houses, the consulates — essentially ceased to exist in a single afternoon.

The city rebuilt, and then on 29 May 1945 it burned again in an air raid. After the surrender, the Allied occupation requisitioned the port and much of central Yokohama, and did not fully release it for years.

What you can actually still see

Very little survives, and the survivors are worth knowing by name. Three towers along the waterfront are known locally as the King, the Queen and the Jack: the Kanagawa Prefectural Government Office (1928), the Yokohama Customs House (1934), and the Port Opening Memorial Hall (1917). Sailors used them to fix their position coming in, and named them like playing cards.

The Red Brick Warehouse — two customs buildings finished in 1911 and 1913 — survived the earthquake in part and now holds shops. The Foreign General Cemetery on the Yamate bluff holds about 5,000 graves from more than forty countries, and reads like a directory of everyone who came here and stayed.