Virtually nothing remains of the old post-town of Karuizawa beneath the growth of today’s resort development. It lies at the northern end of the present town some distance away from the train station, although the highway passes through a popular shopping district which retains the liveliness of an old post-town.
Leaving the built-up area, the road skirts past secluded country villas. At the site of the old masugata entrance to the post-town, there is a stone inscribed with a poem by the poet Basho. The highway now becomes a hiker’s trail which ascends thorough woodland to Usui Pass, the last of the great passes before Tokyo.
The ascent from Karuizawa is sharp but fairly short, climbing to just over 4,000 feet. At the top of the pass is Kumano Shrine, the steps of which are bisected by the boundary between Nagano and Gunma Prefectures. Surrounding the shrine is a cluster of tea housesand, nearby, a viewing platform for the spectacular panoramas of Mt. Asama to the northwest and Miyogi to the south.
After this pleasant pause, the highway begins its long descent to the Kanto plain. At first the path is gentle as the Nakasendo winds its way along the ridge crest. Along the way is an abandoned village and, lower down, the sites of former tea houses. Here, the road is little more than a narrow path in places with steep drops on either side. The final descent into Sakamoto is one of the steepest and most difficult sections of the whole route, for the underlying slate-like rock is loose and treacherous. The trek is worth it, however, for the fine views all around. Finally, after almost nine miles spent entirely on footpath, the next post-town of Sakamoto is reached.