A hike through the hills does a body—and soul—good, and Kusatsu's forested trails certainly fit the bill. The three main courses vary in length from three to sixteen kilometers (roundtrip), providing options for casual to serious hikers. Those in need will find trekking poles and other equipment for rent at the base of the hills.
Along the trails you can spot seasonal plants, such as the brightly colored blossoms of rhododendron, azalea, fringed galax, thistle, heath, scarlet leaved viburnum, and the fluffy heads of tussock cottongrass. The forests are dense with trees, moss, and enough flora and fauna to satisfy nature-lovers and photographers alike.
The shortest of the hikes, the Koridani Hiking Trail, begins near the base of Kusatsu Onsen Ski Resort. Starting near Tenguyama Rest House, the route winds beneath the leaves of Japanese clethra, Mongolian oak, and Japanese larch, Erman’s birch, Japanese rowan, and scarlet leaved viburnum as it ascends the mountainside. Along the trail’s edges, here and there luminous moss grows in shadowy corners and rocky caves.
The Koridani Hiking Trail leads to a cave believed to be a spiritual place that endows visitors with healing energy. The cave is called the himuro, or ice room. True to its name, ice remains in the cave until July, keeping the temperature low and refreshing even during the hottest days of summer. Whether you are a believer or not, the himuro and its environs can give you a taste of ancient Japanese spiritual traditions.
The moderate path of the Koridani Hiking Trail is suitable for all levels, though proper footwear—and sound preparations suitable for changeable weather—are advised.