Tsukumi City (津久見市, pop. 15,815 as of 2020) is a small city in the southwest of Ōita Prefecture. 

Besides having produced a number of champion high school baseball teams and professional athletes—hence the manhole design—Tsukumi is famous for Ōtomo Sōrin (1530 – June 11, 1587), a Japanese feudal lord of the Ōtomo clan and one of the few lords to convert to Christianity. He met personally with Francis Xavier in 1551 and forged an alliance with the Portuguese that culminated in the Siege of Moji ten years later. Ōtomo was also responsible for sending the first official embassy to Europe, known as the Tenshō Embassy, to have audiences with Pope Gregory XIII (the Pope after whom the Gregorian calendar is named) and European kings. Interesting stuff from an otherwise sleepy port town.