What is the second largest city in Japan?

While many might guess Osaka, the title of Japan's second most populous city belongs to the major port located just south of Tokyo. With a population of over 3.7 million, it is a massive urban center in its own right, though its proximity to the capital means it is often seen as part of the Greater Tokyo Area. This close relationship can sometimes obscure its distinct identity and immense scale.

The city's prominence is a relatively recent phenomenon, deeply tied to a pivotal moment in the nation's history. For centuries, it was a sleepy fishing hamlet. That all changed in 1859 when, after more than 200 years of self-imposed isolation, Japan opened its borders to international trade following the arrival of U.S. Commodore Matthew Perry's fleet. Yokohama was designated as one of the first treaty ports available to foreign merchants.

This decision triggered an explosion of growth. The small village rapidly transformed into a cosmopolitan hub as foreign traders, diplomats, and technology poured in. This legacy endures today, visible in the city's international atmosphere, historic Western-style architecture, and one of the world's largest Chinatowns. Its entire modern identity was forged in its role as Japan's primary window to the outside world.