Kusatsu Onsen, located in the beautiful mountains of Gunma Prefecture, is known as one of Japan's top hot spring towns. With the famous Yubatake hot water field, soothing outdoor baths, and the special Yumomi water-cooling show, it offers a unique experience for onsen enthusiasts. After spending two days there, I’d like to share my guide and a two-day itinerary to help you enjoy this wonderful onsen town.