I went to the Seki Hamono Matsuri (Seki Cutlery Festival) to buy myself a nice cooking knife and to have fun. While there, I dropped by the shrine. On that day, they also had an exhibit of old clothes and masks that you could go inside and see. They’re old enough that everyone who went in to see had to wear a surgical mask to protect the items from humidity and germs.
If you’re in Seki visiting the Sword Tradition Museum, you should definitely go next door and check it out.