the seven districts of ancient Japan
Historical term referring to the seven major administrative regions (道) of Japan under the Ritsuryō system: Tōkaidō, Tōsandō, Hokurikudō, San'indō, San'yōdō, Nankaidō, and Saikaidō.
Under the Ritsuryō system, Japan was divided into the seven districts.
the five home provinces and seven districts of ancient Japan
From 七 (seven) + 道 (road, circuit, administrative region). The term originates from the ancient Ritsuryō administrative divisions.