Chiba Prefecture (千葉県 Chiba-ken) is a prefecture of Japan located in the Kantō region and the Greater Tokyo Area. The sixth most populous prefecture, and 27th largest by land area, Chiba is on the East coast of Honshu and largely consists of the Bōsō Peninsula, which encloses the eastern side of Tokyo Bay. Its capital is Chiba City.
Chiba Prefecture borders Ibaraki Prefecture to the north at the Tone River, Tokyo and Saitama Prefecture to the west at the Edo River, the Pacific Ocean to the east and Tokyo Bay around its southern boundary. Most of Chiba lies on the hilly Boso Peninsula, a rice farming region: the east coast, known as the Kujūkuri Plain, is an especially productive area. The most populous zone, in the northwest of the prefecture, is part of the Kantō region that extends into the urban agglomeration of Tokyo and Saitama. The Kuroshio Current flows near Chiba, which keeps it relatively warm in winter and cooler in summer than neighbouring Tokyo.