Guests who stay at a ryokan in Kinosaki Onsen can visit all seven public baths for free. But daytrippers like me have to pay admission for each one, costing ¥600 or ¥700.
However, they have a public bath day pass for only ¥1,200 (外湯めぐり券). Use it to enter all seven. Great deal! Definitely one of the best bargains in Japan!