Located in the north-central part of Kumamoto Prefecture, Mashiki Town in Kamimashiki District is bordered by Kumamoto City to the west, Kikuyo Town to the north, Nishihara Village to the east, and Mifune Town to the south. The town's flat, low-lying area is believed to have been an inlet in ancient times. Early mold-patterned pottery has been excavated at the Kushishima Site, and a large amount of black, polished pottery known as Koga-style pottery has been excavated at the Koga Site, making this style of pottery the last of its kind in the Kyushu region. During the Sengoku period, many castles were built here, including Kiyama Castle, Akai Castle, and Tsumori Castle. It has a history of being a strategic location for forces seeking to expand into Higo, where numerous battles were fought. The town's specialty crops include watermelons and melons.