【Autumn Foliage Drive】Exploring "Sanno Mountain Road" right after its opening and "Nikko Irohazaka (downhill)"! Also a pilgrimage to Initial D

In mid-October 2025, I headed south from the Kawamata Onsen area to check the autumn leaves in the popular Oku-Nikko area. The condition of Sanno Mountain Road, which is temporarily opened during this season, is a must-see! Please refer to this for the state of the foliage and for driving on the mountain road.

Heading towards the first Irohazaka from the Sanno Forest Road

This route is chosen due to the interview schedule, progressing from the Kawamata Onsen area along the Oku-Kinu Sanno Forest Road, passing through the first Irohazaka, and heading towards Tokyo. I'm looking forward to seeing what kind of scenery awaits.

The Oku-Kinu Line "Sanno Forest Road" is a forest road connecting Kawamata Onsen and the Kōtoku area near Senjōgahara, which will have limited access lifted from October 1, 2025, to November 30, 2025.

This is the starting point of the Sanno Forest Road on the Kawamata Onsen side. On this day, being a weekend, vehicles and motorcycles were passing by at fairly short intervals, which is unusual for a forest road. Keeping my focus, I continued towards the pass at the summit.

Since I'm traveling from the opposite side against the major route coming from Senjōgahara, I encountered other vehicles frequently, and the presence of ditches hidden by fallen leaves added a sense of ruggedness. I also felt somewhat apologetic towards the cars and motorcycles coming from the opposite direction who were giving way on the narrow road.

I reached the conservation monument of Sanno Forest Road located at an altitude of about 1600m. The path opens up from a road covered by trees, giving a sense that the summit is near.

Towards the Kōtoku side, where the autumn leaves can be enjoyed more easily,

I could see the mountains welcoming the autumn colors from the road. Surrounding the forest road are Mount Tarō and Mount Takanagi, and the mountains visible from the road appeared to be quite colorful. Since there's still a lot of green, it seems that we will be able to enjoy even more autumn colors from now on.

After casually crossing the Sanno Pass and continuing further towards the Kōtoku side, a breathtaking view unfolded before me. The orange slopes of Mount Tarō visible to the right had countless birch trunks and branches that looked like white radiating patterns, creating a landscape of stunning beauty. If you want to enjoy the autumn colors from the forest road, the Kōtoku side might be more recommended.

The scenery near the end point of the forest road was also magnificent, with straight, tall larch trees spreading across my field of vision, and as the autumn leaves progressed, the leaves were illuminated by the sun, shining in bright yellow-green. The Sanno Forest Road is a very enjoyable route, with the vegetation changing dramatically in different areas.

Passing through the Oku Nikko area, we head toward the first Iroha-zaka

The battle field of Senjogahara is bustling with tourists, and after passing through Lake Chuzenji, we make our way to Iroha-zaka. The image is from the vicinity of Senjogahara, and the autumn leaves on this day seem to be at their peak. Lake Chuzenji still has some time to go.

We arrive at the first Iroha-zaka, which is for descending only. There isn't much congestion, and it feels like the autumn foliage is still on the way. I doubt it will be this smooth during the peak foliage season.

Finally, we wrap up with a pilgrimage to the holy site of Initial D

Changing the subject, actually, this first Iroha-zaka is a holy site for Initial D, and it serves as the stage for the battle featuring my favorite character, Kyoichi Sudou. This bridge is located just before the climax of the battle, and I felt a thrill when I realized it was a holy site all by myself.

In the work, the third bridge is approached side by side, and the difference becomes clear at the narrow exit where the road width decreases. Although under construction, there is indeed a sign indicating the width reduction, and it has been confirmed that the detailed course layout is consistent with the work, which is very satisfying.

I came for the autumn foliage survey but also got to do a pilgrimage to the sacred sites, making it a very enjoyable drive. I highly recommend taking this route to enjoy the autumn leaves in Nikko during the upcoming season.

Interview/Text by Kazuma Tanaka

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