noun
Usui Pass
A mountain pass in Japan, historically important as a route between Gunma and Nagano prefectures.
碓氷峠は、群馬県と長野県の県境にある峠です。
Usui Pass is a mountain pass on the border between Gunma and Nagano prefectures.
The name is derived from the location; the exact origin of the kanji is uncertain.