Fourtreat Kusatsu - Adult Only  

In Kusatsu, just minutes from the city center, Fourtreat Kusatsu sits as an adult-only retreat in Japan’s famed onsen region. Jigokudani Monkey Park is about 28 miles away, Mt. Kusatsu Shirane is roughly 8.6 miles off, and Matsumoto Airport is 67 miles by road.

The vibe is low‑key and grown-up with modern, simple rooms that include air conditioning, flat-screen TVs and a work desk. Bathrooms are shared and come with a shower, free toiletries and a hairdryer, and the property offers private check‑in/out and a safe‑deposit box.

Soak in the hot spring (onsen) bath or unwind in the sauna after a day on the trails. The hotel also has a lively bar, an on-site restaurant and free private parking for guests.

Free WiFi throughout the property and in-room desks make it easy to work or plan your next outing.

An on-site restaurant serves meals and the bar provides a relaxed evening atmosphere — perfect for a nightcap after the onsen.