Kusatsu was immediately one of our favorite places in Japan. For Japanese people, it's a famous hot spring resort town in Gunma prefecture. For foreigners it's relatively unknown.
Like many resort towns in Japan, Kusatsu is built around the numerous hot springs in the area. One of the first things you'll notice about Kusatsu is the pungent smell of sulfur in the air. The hot springs in Kusatsu are said to be some of the most therapeutic in Japan with a high concentration of minerals in the water, and of course, the sulfur content. It is said that the water there can cure every sickness except love sickness.
Kusatsu is centered around the other worldly yubatake (hot water field), which is the source of the hot spring water for the ryokans (traditional inns) in town. The water is shuttled down wooden chutes to cool it off before funneling it in different directions.
There are various shops and restaurants surrounding the yubatake, and a covered foot bath, which is a perfect place to relax and watch visitors to the town wander around wearing their yukata (summer kimono) following a dip in the hot spring.
The town is small and easily walkable from whatever ryokan you are staying at. All of the main roads fan out from the yubatake, making it nearly impossible to get lost. These roads host a variety of shops selling manju (pastry filled with red bean paste), small souvenirs, local sake, and salted fish.
Beyond the center of the town there are other restaurant and bar options, but since most visitors to Kusatsu take dinner at their ryokan, many restaurants close early. There are a handful of izakayas (pubs) that are open later than everything else, and are a good choice if you want to have a couple drinks and small plates of bar food.
Just a short walk from the center of town, and past the shops selling manju (and giving free samples away!), is a shrine and park with hot spring water flowing through it. Of course, there's another foot bath to enjoy as well! A set of stairs leads up from the park, and if you follow it long enough you'll reach the nearby ski resort.
To access Kusatsu from Tokyo you can take a bullet train from Tokyo Station to Takasaki Station. From there, transfer to the Agatsuma Line and take that train to Naganohara-Kusatsuguchi Station. Then walk one minute to the bus terminal, and ride the bus form 30 minutes to Kusatsu Onsen Station. The center of the town is only a two minute walk from the bus station.
The whole journey takes about 3 hours and 45 minutes. Of course time will be added if you don't leave from Tokyo Station, or if your connections between trains are not tight.
Kustatsu isn't the easiest location to reach, but if you're interested in rural Japan it's an unknown gem for tourists from out of the country, and a Session Japan favorite. We love it, and we think you will too.