https://www.google.com/maps/@36.1150...7i13312!8i6656
Norikura Skyline in Gifu Japan. It is closed to traffic in the summer except buses. It is a mecca for Japanese cyclists.
You can do a loop up the Skyline and down 158 back into Matsumoto.
The route out of Matsumoto is 34.5 miles , 9000 ft of climbing.
158 descent will be white knuckle with traffic and tunnels.