Last Updated: Feb 6, 2023

Kusatsu Onsen

One of Japan’s Best Hot Spring Towns

Nestled 1,200 meters above sea level in the mountains of Gunma Prefecture, the rustic town of Kusatsu Onsen is a hidden gem that goes unnoticed by many visitors to Japan. Considered to be a top hot spring in Japan, its location away from any major train lines has kept it from becoming popular with international tourists. That said, if you’re looking to experience a traditional Japanese onsen town, I can think of no better choice than a visit to Kusatsu Onsen.

As an onsen town, the health benefits of Kusatsu Onsen’s waters are legendary. A soak in the sulfuric waters is said to have the potency to cure any and all ills save for a broken heart. Furthermore, in the late 1800’s German doctor Erwin von Baelz even recognized the rejuvenative powers of Kutasu. It is said that the hot springs of Kusatsu Onsen are so acidic that they can dissolve a 6-inch nail in under ten days; hence, you can imagine the survival rate of harmful bacteria.

Each minute more than 32,000 liters of heated spring water gush from their source at Mt. Shirane, a still-active volcano. To put that number in perspective, imagine 230,000 barrels full of hot spring water! The sheer volume of the flow allows for the large number of facilities in Kusatsu Onsen and the city claims to have one of the most plentiful springs in Japan. Unlike other areas, the waters of Kusatsu Onsen are never diluted, reheated, or otherwise adjusted which only serves to bolster their impressive healing capabilities.

Compared with other popular onsen towns, Kusatsu Onsen is a bit of a hassle to get to but the rustic vibe of the area, coupled with its impressive scenery, make the journey worth it. Given its remote location, getting to and around Kusatsu Onsen can be intimidating even for long term residents but fret not; in this guide I have included any and all information you might need to get the most out of your stay.

Note: If you’ve never been in one before, check out my ultimate onsen guide first before going to Kusatsu!