Usui Pass

36°20′41″N 138°39′03″E / 36.3446°N 138.6507°E / 36.3446; 138.6507

A 489 series with JNR Class EF63 helper engines, 1997

The Usui pass (碓氷峠, / Usui-tōge) is a mountain pass that lies between Nagano and Gunma Prefecture in Japan. It has served as one of the major transportation routes in central Japan since at least the eighth century.