[4] Nakasendo was constructed by Tokugawa shogunate, the mount pass belonged to the road.

It is one of the most defensible chokepoints of the road because of heavy snow and precipitous topography.

In 1925, 和田嶺自動車 (Wada Peak Automobile Road) was established and ran through this mount pass.

But, this road was closed during winter due to heavy snow, so in 1933, Wada Pass Tunnel was constructed.

Wada Pass Tunnel is narrow, so vehicles are not able to run as two lanes.