History of the Road through Shimizu Pass
In the sixteenth century, people began traveling to Echigo Province (now Niigata Prefecture) and Kōzuke Province (now Gunma Prefecture) via Shimizu Pass. This route functioned as an alternative to a longer, previously established route that crossed the mountains via the Mikuni Pass to the northeast.
Uesugi Kenshin (1530–1578), the powerful warlord and provincial governor of Echigo, is known to have crossed the Mikuni Mountains at least 13 times, but he always traveled via the Mikuni Road to avoid the heavy snow and steep slopes of Shimizu Pass. However, Kenshin recognized the importance of the more direct route through Shimizu Pass, and he had a castle built along it. In 1632, the Tokugawa shogunate (1603–1868) closed the pass and erected checkpoints on both sides at Yubiso and Shimizu as part of a large-scale restructuring of the road system. Merchants in Edo (now Tokyo) and neighboring domains repeatedly appealed to the shogun to reopen Shimizu Pass, but it remained closed.
In 1872, the old official highway system was abolished, and in 1874 the prefectural governor reopened the pass as the New Shimizu Road. In 1885, it was then renovated and leveled to accommodate horse-drawn carts and became National Route 8. However, the road was quickly degraded by the harsh environment, and by 1888 it had become largely unusable. Afterward, certain sections were renovated again, and together with a section of the road on the Niigata side it was operated as a toll road. That road was heavily used until the end of the Meiji era (1868–1912).
In 1920, the road through the pass was downgraded to a prefectural route. In 1970, it was upgraded again to become National Route 291. Today, the section of the toll road on the Niigata side and everything above Ichinokurasawa has been incorporated into the hiking trails. Relics of travel through Shimizu Pass, such as old stone walls, can still be seen along the trails.