Usui Pass
Coordinates: 36°20′41″N 138°39′03″E / 36.3446°N 138.6507°E
The Usui Pass (碓氷峠 Usui-tōge?) is a mountain pass that lies between Nagano and Gunma Prefectures in Japan. It has served as one of the major transportation routes in central Japan since at least the eighth century.
The pass on the ancient Tōsandō highway was described as early as the 8th century, in the Nihon Shoki, as Yamato Takeru went through the pass during his journey in eastern Japan. Later, the Nakasendō, one of the five routes of the Edo period maintained by the Tokugawa shogunate (and one of the two that connected Edo, modern-day Tokyo, to Kyoto) followed the route through the pass.
The modern National Route 18, which goes through the pass, serves as a major link between the popular tourist spot Karuizawa and the Kantō plain (including Tokyo). A bypass and an expressway now make the trip faster and safer. The original road still exists as of 2013.
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