Kaizu is a city located in Gifu, Japan. As of 1 April 2018, the city had an estimated population of 34,960, and a population density of 310 persons per km2, in 12,167 households. The total area of the city was 112.03 square kilometres (43.26 sq mi). Most of the city is located at sea level and is well known for levees surrounding the area.