The Pool at Hotel Okura Kyoto
The pool at Kyoto Hotel Okura is referenced by reviewers writing for major publications. Out of 9 professionals tracked on TripExpert, 3 referenced the pool, such as Oyster, Star Service and Forbes Travel Guide.
Hotel Okura Kyoto 
Oyster
Star Service
Forbes Travel Guide
Oyster "By comparison, the similarly priced Hotel Granvia Kyoto is larger, more modern, and includes an indoor pool and an underground shopping mall"
Star Service "The whirlpool, sauna and three-lane, 20-m pool are open to hotel guests only 7-10 am, at steep fees to boot, though the private health club admits hotel guests later in the day if there's room (people younger than 20 are not allowed), at even steeper fees"
Forbes Travel Guide "There is a good-sized swimming pool and adjoining Jacuzzi, along with sauna, male and female baths and a relaxation area"
