Soma-kaido Highway (杣街道)
Soma-kaido Highway was a highway that existed in the Edo period between Shiga Prefecture (Omi Province) and Koka County. It was also called Somakai-do Road and Shinkai-do Road.
This route along Soma-gawa River was the equivalent of Tokai-do Road (route connecting Nara and Kanto area) during the Omi Court period and was also called 'Kurabu-do Road.'
It was destroyed after the Jinshin Uprising but used as Tokai-do Road until the route was changed to 'go over Asuha' via Suzuka Pass in 886 during the Heian period. The route continued to be important for the people of Soma-dani Valley as the 'Iga-michi Road' from Konan to Iga, as the route for pilgrimage to Ise Shrine, and as the road for Yamabushi (mountain priests).
In the 17th century, in the Edo period, most of the current route that separates from Tokai-do Road at Mikumo and stretches to Iga seems to have been established and in a 1742 document, there is a reference to 'Somakai-do Highway.'
The current route was serviced around 1887 and it was called Shinkai-do Road at the time. Kansai Railway was built along the route in 1889. It was nationalized in 1907 and is now the JR Kusatsu Line.
Mikumo (Konan City) - Sanbonyanagi (Minakuchi, Koka City) - Fukagawa Market (Konanncho, Koka City) - Terasho (Konancho, Koka City) - Ohara Market (Kokacho, Koka City) - Ueno (Kokacho, Koka City) - Tsuge (Tsuge-cho, Iga City, Mie Prefecture)