Sasebo Naval Arsenal was one of four principal naval shipyards owned and operated by the Imperial Japanese Navy.

Sasebo is a core city located in Nagasaki Prefecture, Japan. It is the second-largest city in Nagasaki Prefecture, after its capital, Nagasaki. On 1 June 2019, the city had an estimated population of 247,739 and a population density of 581 persons per km2. The total area is 426.06 km2 (165 sq mi).