Marukin Soy Sauce Museum
Since its establishment in 1907, Marukin Soy Sauce has been producing soy sauce with a flavor suited to the times while utilizing traditional methods in a natural brewery for more than 100 years. One of the buildings has opened to the public with a memorial commemorating the 80th anniversary of the company's founding in 1987. The gassho-zukuri building, the largest of its kind in Japan, is registered as a national tangible cultural property.
Marukin Soy Sauce has both a warehouse and a factory. Starting from the factory, there are all kinds of diagrams explaining how soy sauce is made. I really learned a lot about the process. It was awesome!