This is an 8-postcard set from Takaragawa Onsen. Takaragawa Onsen, located further north of Minakami Onsen in Gunma Prefecture, is a hot spring area with only one ryokan (Japanese inn) called Osenkaku. This postcard set was obtained during a family trip in the early Heisei era. It's a natural hot spring inn with men's baths, women's baths, and mixed bathing. These postcards are somewhat special, as they were featured in "Kasuhaga no Sekai" (Chikuma Bunko), a book by the multi-talented writer and artist Jun Miura, which brought them some fame. The book humorously introduces postcards sold at famous scenic spots in Japan and around the world. They show signs of aging and have yellowed. There don't seem to be any similar items listed on Mercari. They are, in a way, a rare item. *Important Notes: The 9th image in the listing is a reference image from "Kasuhaga no Sekai" as mentioned above. Please note that this is NOT included in the sale and is only for reference. It will not be included in the postcard set even if you purchase it. Thank you for your understanding.