Shima Onsen by Bicycle: Lake, Hot Springs & River — 2 Days

A 2-day cycle through Gunma's hot spring town, featuring Lake Okushima and the Shima River valley

Shima Onsen sits in the northwestern reaches of Gunma Prefecture within Jōshin'etsu-kōgen National Park, a hot spring settlement where bicycles—most equipped with electric assist—serve as the primary means of travel. The town occupies terrain that alternates between valley floor and modest hills, making pedal-assisted bikes practical for covering ground between the town center, the Oketsu (Giant's Kettles) formations roughly 3 kilometers distant, and Lake Okushima about the same distance beyond. The lake itself is known for its distinctive blue-green coloration, particularly visible in deeper sections, while the surrounding Shima River runs clear and shallow in places. Spring through fall brings a range of water-based activities—canyoning through a seven-waterfall gorge, stand-up paddleboarding, and canoe tours—though the bicycle remains the quieter option for independent movement. A single overnight stay anchors the circuit, with thermal bathing as the evening centerpiece and pottery workshops, small cafés, and local craft shops available as supplementary activities.

Highlights

Cycling to the Oketsu (Giant's Kettles), a natural river formation 3 kilometers from the town center where the Shima River displays layered color gradation
Lake Okushima by bicycle, a 4-kilometer loop accessible via electrically assisted bike, with views of Shakunage Falls and seasonal foliage
Yamaguchi Kawara-no-Ashiyu foot bath, a riverside soaking point within the hot spring town
Hinatami Yakushido, a historical temple structure believed to house the source waters of Shima Onsen
Canyoning through a canyon in the Shima River (June–September, ages 13+)
Stand-up paddleboarding or canoe touring on Lake Okushima (June–October, varies by activity and age)
Pottery creation and decoration workshops in the town center

Day by day

1Arrival & Cycling to Oketsu and the Shima RiverShimanekki · Oketsu (Giant's Kettles) · Gallery Café · Yamaguchi Kawara-no-Ashiyu foot bath · hot spring town

Arrival at Shima Onsen typically occurs around midday. Bicycles can be rented through Shimanekki (1 hour at 500 yen, overnight at 3,000 yen) or the Shima Onsen Association (2 hours at 500 yen, plus 200 yen per additional hour). Most rental stock includes electric-assist models, which materially ease passage through the town's sloped terrain. After settling in, a meal of Gunma Okirikomi udon noodles or Yaki manju—steamed wheat cakes finished with a sweet miso glaze—provides local fuel. The first cycling destination lies approximately 3 kilometers from the town center: the Oketsu (Giant's Kettles), a series of natural rock formations carved into the Shima River. The ride passes through mixed terrain and woodland. The Oketsu site itself displays the river's color gradation effect—water appears blue in deeper pools and translucent in shallower sections. A Gallery Café operates adjacent to the formation, offering a break point with views of surrounding woodland or, seasonally, fall foliage. The return to town follows the same route. The Yamaguchi Kawara-no-Ashiyu foot bath, situated within or very near the hot spring town proper, provides a place to soak tired feet while seated beside the river. Evening accommodation is arranged within the hot spring town, where thermal bathing concludes the day.

2Lake Okushima Loop & Return Through Historic Temple GroundsLake Okushima · Shakunage Falls · Hinatami Yakushido · Hot Spring Street district · town center

The second day begins with travel from the hot spring town toward Lake Okushima, approximately 3 kilometers distant over terrain that includes several hills—a route where electric-assist bicycles prove their utility. Morning light and green-season conditions are reported as optimal viewing times for the lake, which displays color variation depending on season and time of day. Lake Okushima features a 4-kilometer cycling loop that allows for self-directed route-finding and photography. Shakunage Falls marks a notable stop along the loop; the waterfall site is positioned to capture negative ions in the surrounding air. On the return journey toward town, a detour to Hinatami Yakushido, a temple structure located at a modest distance from the main lakeside route, adds historical context—the building stands above the reported source point of Shima Onsen's thermal waters and offers a quiet stop. The site holds seasonal appeal, particularly during cherry blossom season in spring. The Hot Spring Street district in the town center contains gift shops stocked with local confectionery, sake, regional craft beer, and folk handicrafts specific to the area. A final café break concludes the circuit before departure. The route between these points remains suitable for bicycle travel, though cumulative distance and terrain elevation over two days should be gauged against individual fitness levels and electric-assist battery capacity.