Japanese hot spring retreat KAI Hakone—part of the Hoshino Resort group—is now open offering a unique indoor-outdoor bath (with one open wall), allowing clear views of the woods surrounding the hotel.

Rooms start at JPY 29,000 (S$365). Water at the facility is kept at temperatures between 30 and 80 degrees Celscius, which is believed to help with joint pain and chills.

The getaway is on the banks of the Sugumo River, just a 45-minute bullet train ride from Tokyo. There are almost 50 rooms, outfitted with chic modern tatami mats. On-site, there’s also a dining room serving fresh sashimi from the nearby Pacific Ocean and a cozy library, with about 100 books. Hakone, in the Kanagawa Prefecture, is famous for its hot springs at traditional ryokans.

Find out more at the Hoshino Resort website.