Lake Okushima: Shima Onsen Hot Springs' Spectacle of Cobalt-Blue

About Shima Onsen Hot Springs & Lake Okushima

Shima Onsen Hot Springs locates in Gunma prefecture’s northwestern Agatsuma region. The hot springs has a history of over 1200 years, and has over 42 springs releasing the hot natural waters. The waters are soft, and can help relax nerve pains and relieve exhaustion. In 1954, Shima Onsen was designated as Japan’s first “People’s Recreation Spa/Onsen”.

Lake Okushima

Lake Okushima

About 4 km of north of Shima Onsen is Lake Okushima. The lake is a result of the dam placed in Shima River, and is famous for its exceptionally vibrant, blue water.

Lake Okushima’s cobalt blue waters

The reason behind the color of the water is yet to be discovered. You can walk around the lake to enjoy the hues of blue from many different angles.

Shima River

Shima River’s waters

Shima River runs down the Shima River Valley area. It is classified as a “Class A River” according to Japanese law, meaning it is relevant to the country’s economy and as a symbol of nature conservation. The mesmerizing blue color of the river is commonly referred to as “Shima Blue”. The river’s current is not too strong, so you can splash around in it in during the warmer months.

Sights & Experiences around Lake Okushima

Shima Potholes

The potholes

In one area on the Shima River, you can find 8 potholes. The potholes are created by a stone circling along a small crevice on the river ground.

The water in the pothole

These potholes are designated a Cultural Important Property, with one of them measuring as big as 3.2 km deep.

Kamagafuchi Abyss

You can find Kamagafuchi Abyss in Shima River’s narrower areas. The flow of the abyss was once much more rapid, but has gotten weaker in recent years due to the construction of dams upstream. Because of the rapid flows in the past, the rocks in this area are more sharply eroded down.

Outdoors Experiences at Lake Okushima

Shima Onsen area is surrounded by all kinds of nature, and is a paradise for adventurous visitors. You can go canoeing, canyoning, water-sliding and more, right by the beautiful blue waters.

The 4 Seasons of Shima Onsen Hot Springs

Spring

Cherry blossoms by Lake Okushima

During the springtime, many different kinds of flowers bloom throughout the Shima Onsen area. Due to the Agatsuma area’s high altitude, the spring flowers blossom about a month later compared to when it would in Tokyo. Visit between late April and late May to see trees and trees of cherry blossoms with the Shima Blue lake.

Summer

Lake Okushima in the summer

Summer at Shima Onsen is cool and comfortable. Go fishing by the river or break a sweat canyoning! Also during the summer, you might be able to run into animals such as the antelope or flying squirrel.

Autumn

Fall foliage by Lake Okushima

Catch the fall foliage at Shima Onsen from late October to early November. Ride the canoe on Lake Okushima and enjoy the fall colors from there!

Winter

Photo by visitgunma.jp

Warm up in the winter by taking an outdoor bath at Shima Onsen. Although the area will be pretty cold and covered in snow, the snowy view is breathtaking. Another winter specialty is partially frozen Lake Okushima, which blends its usual vivid blue with a frozen layer of snow-white ice.

Events near Lake Okushima

Tori-oi Festival (Jan.)

Tori-oi Festival, literally translating to “bird-chasing festival”, has a history of over 400 years. The festival originated as an event to chase birds away from ruining the locals’ crops and to celebrate a successful harvest and household safety. The taiko drums used in this festival are designated as a prefectural important cultural property.

Access

Nearest station: Shima Onsen (bus stop)

From Tokyo Station

【Tokyo Sta.】Kanetsu Transportation Highway Bus / for Shima Onsen
→【Shima Onsen】→ about a 30-minute walk

From Maebashi Station

【Maebashi Sta.】JR Ryomo Line / for Takasaki
→【Shin-maebashi Sta.】JR Agatsuma Line / for Kazawaguchi
→【Nakanojo Sta.】Kanetsu Transportation Local bus / for Shima Onsen
→【Shima Onsen】→ about a 30-minute walk

Shima Onsen Hot Springs & a Scenic Time of Slow Relaxation

The area around Shima Onsen Hot Springs has a variety of places where you can enjoy the hot springs, and retro vibes. Just a short trip away, though, is a myriad of vistas including the Lake Okushima. The cobalt blue of Lake Okushima seems to change with every visit, offering an indefinitely number of experiences. Near the Shima potholes, you will also find "Forest Cafe KISEKI", where relaxing terrace seating offers a grand view of mother nature.

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