sentences:  Prefectural government functions include the organization of the prefectural police force, the supervision of schools and the maintenance of prefectural schools (mainly high schools), prefectural hospitals, prefectural roads, the supervision of prefectural waterways and regional urban planning.Their responsibilities include tasks delegated to them by the national government such as maintaining most ordinary national roads (except in designated major cities), and prefectures coordinate and support their municipalities in their functions.De facto, prefectures as well as municipalities have often been less autonomous than the formal extent of the local autonomy law suggests, because
  
  Historically, during the Edo period, the Tokugawa shogunate established around the nine largest cities in Japan, and 302 elsewhere.