Shimōsa Plateau
During the militarization of northern Chiba Prefecture that began in the early 20th century, the eastern area of the plateau was declared a military zone. The Shimōsa Plateau was a center of the manufacture of war goods, notably of munitions and military aircraft, and saw the construction of numerous military facilities. Shimofusa Air Base was constructed in 1945 by the Imperial Japanese Army Air Force on the border of Kashiwa and Kamagaya. Most of the military facilities and industrial areas on the Shimōsa Plateau were destroyed by Allied bombing during World War II.