Find out why 3 million visitors are flocking to hot springs in the small Gunma town of Kusatsu.

Set amid rolling, misty hills 90 miles northwest of Tokyo, the town of Kusatsu is centered on a giant hot water field known as the yubatake, which collects and cools the hot spring water bubbling up from the ground underneath. Some of the town’s many shops, hotels, and restaurants were built around the yubatake, where visitors can slurp soba noodles, drink hot sake, and watch illuminated steam drifting through the town at night.

For yumomi, water steaming at 65 degrees Celsius is stirred with large wooden planks until closer to 48 degrees. While this would still be too hot for bathing, the high acidity levels and hydrogen sulfide concentration in the water make it palatable. You can watch daily yumomi performances in the Netsunoyu building beside the central yubatake. Additionally, there are plenty of onsen and ryokan (traditional inns) in Kusatsu where you can try the most popular Japanese bathing style, soaking in open-air baths called rotenburo.