San'indō

San'indō (山陰道^?, literally, "northern mountain circuit" or "northern mountain region") is a Japanese geographical term. It means both an ancient division of the country and the main road running through it.San'in translates to "the shaded side of a mountain", while dō, depending on the context, can mean either a road, or a circuit, in the sense of delineating a region. This name derives from the idea that the northern side of the central mountain chain running through Honshū was the "shaded" side, while the southern side was the "sunny" (山陽 San'yō) side. The pre-modern region corresponds for the most part with the modern conception of the San'in region.

The region was established as one of the Gokishichidō (Five provinces and seven roads) during the Asuka period (538-710), and consisted of the following eight ancient provinces: Tamba, Tango, Tajima, Inaba, Hōki, Izumo, Iwami and Oki. However, this system gradually disappeared in the centuries leading up to the Muromachi period (1333-1467).

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