Hamamatsu is a city located in western Shizuoka Prefecture, Japan. In September 2023, the city had an estimated population of 780,128 in 340,591 households, making it the prefecture's largest city, with a population density of 500/km2 (1,300/sq mi) over the total urban area of 1,558.06 km2 (601.57 sq mi). The city ranked first in the happiness index of Japan's government-designated cities, publis…