Hamamatsu is a city located in western Shizuoka Prefecture, Japan. As of 1 December 2019, the city had an estimated population of 791,707 in 340,591 households, making it the prefecture's largest city, and a population density of 508/km². The total area of the site was 1,558.06 km². Hamamatsu is a member of the World Health Organization’s Alliance for Healthy Cities.