Tama River
Ōme is located in the Okutama Mountains of western Tokyo, bordered by Saitama Prefecture to the north. The Tama River runs from west to east almost in the center of the city area, and the Kasumi River and Naruki River, which are tributaries of the Iruma River (Arakawa River system), also flow from west to east in the north. The geography changes from the flat land in the east to the hills and mountains in the west. The highest point is 1,084 meters on Mount Nabewariyama on the right bank of the Tama River in the western end of the city.