Akima Tunnel
Akima Tunnel (Akima tonneru) is a tunnel on JR's Hokuriku Shinkansen located between Takasaki city (Gunma Prefecture) and Karuizawa town in Nagano Prefecture with total length of 8.295 km. It was built and completed in 1997.
Tunnel data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).