If you are wondering where to go for a day or overnight trip (via one of the local onsen ryokan), look no further than Kiso Valley. A place where you will experience what kind of magical place old Japan was like and feel like you’ve been transported back to the past!
Kiso Valley is situated between the mountains of the Japanese Alps, in Nagano prefecture. It can be reached via JR Nagiso Station and a bus ride, which overall takes around 3 to 5 hours from Tokyo, depending on which route you take. This place is also covered by the JR Flexible East Pass (whereby you will be able to choose any 5 days within a 2 weeks period to take the JR lines and Shinkansen), so if you have the pass and not sure where to go and fully utilize them then definitely consider Kiso Valley. It can be reached via Nagiso Station and if you are using the JR East Pass then go for the northern route via Matsumoto or Nagano because the east pass doesn't cover Nagoya route part! Kiso Valley was an important trade route area during the kingdom periods, and there are a number of post towns along this route, including Tsumago, Narai and Magome. They have been well preserved so that everyone can come and experience what was it like during those times.
The Nakasendo Hiking path is also available if you want to experience what was it like to trek in the olden days. This path connects Tsumago and Magome and, again, it has been well maintained. It should take around three hours to complete the entire path. If you are bringing heavy bags, there is a baggage forwarding service through the towns' Tourist Information Centers. Luggage must be dropped off at the information center between 8:30am and 11:30am and will be delivered to the other town's information center by 1 pm. The cost is 500 yen per baggage. It is available daily from mid-March through November. It is highly recommended that you do this walk if you have the time and it is definitely worthwhile!
Regarding the post towns, they were developed because during the Edo Period. The Shogunate forbid people from travelling and, as a result, people would have to walk from one town to another. The longer these walking routes became, the more of these post towns emerged, helping provide accommodations and food for travelers.
One of the more popular towns is Tsumago and it has been preserved really well. You will feel like you are in the old Japan as you walk through this small town. The houses, road and everything else has that ancient feel to it. Give Kiso Valley a visit if you can: it is one of those place not to be missed if you have the time to make the trip.