I visited the Tomioka Silk Mill as a day trip from Tokyo including a visit to the Snow Monkeys 1 hour further away towards Nagano.

I haven't seen many industrial UNESCO sites yet and I must say that I really enjoyed visiting the Tomioka Silk Mill. Maybe some would say it's not interesting and I can understand why. There is just a small exibition, one building with the (modern) reeling machines, and everything else can just be seen from the outside. My kids were with me and I could only convince them to join me if we also included the Snow Monkeys in Jigokudani on the Japan itinerary we were following.

I drove by car as it was more efficient for the day. Parking is available (paid) just 200 meters from the entrance. As with most place in Japan in found the entrance quite steep but then, they do good maintenance. One of the large storage halls was completely covered and taken apart plank by plank. They really do a good job preserving all as with the reeling machines. Coverd with plastic for the most part! Gave a bit of a sterile feeling.

I do understand why it's UNESCO and I think if they open up a bit more of the buildings. Maybe the managers house with furnuture of that time it will make it even more interesting. If you're in Tokyo and want to get out this is a site worth checking out for sure!