Nakanojo, Gunma / 四万ブルー（四万湖・奥四万湖）
Shima Blue (Lake Shima and Lake Okushima)
Lake Shima at the gateway to Shima Onsen and Lake Okushima at its innermost end are dam lakes created by the Shimagawa and Nakanojo dams. Their greatest feature is the water, whose colour changes several times a day with the light and time: cobalt, indigo and turquoise, a world of blue called "Shima Blue". In the green season SUP and canoe tours are popular, and there are autumn leaves in autumn and snow scenes in winter.
Last official check
27 Sept 2026
Traveler reports
0
Reports open in Phase 2
Next scheduled check
26 Dec 2026
Decide before you go
A short summary made from the official facts below. Check the rows for details.
- Getting there
- Train / Bus
Before you go
Only facts we confirmed on official sources are shown. Anything else is marked “Not checked yet”.
- Opening hours
Not checked yet — we have not confirmed this on an official source yet. Check with the spot before you go.
- Closed
Not checked yet — we have not confirmed this on an official source yet. Check with the spot before you go.
- Admission
Not checked yet — we have not confirmed this on an official source yet. Check with the spot before you go.
- Getting there
Lake Shima: about 15 minutes by bus from Nakanojo Station (JR Agatsuma Line); Lake Okushima: about 40 minutes by bus from Nakanojo Station, then about 2.7 km by rental bicycle or COMS electric car.
Checked 27 Sept 2026 on the official site- Parking
Lake Shima: free, about 20 spaces; Lake Okushima: about 30 spaces, plus 90 at Hinatami Park below the dam.
Checked 27 Sept 2026 on the official site- Payment
Not checked yet — we have not confirmed this on an official source yet. Check with the spot before you go.
- Accessibility
Not checked yet — we have not confirmed this on an official source yet. Check with the spot before you go.
Found wrong or outdated information? Let us know
Address: Nakanojo, Gunma (Japanese address: 群馬県（四万湖）吾妻郡中之条町四万（奥四万湖）吾妻郡中之条町四万)
Official site: https://gunma-kanko.jp/spots/13
Location
Smaller pins are other spots nearby.
Nearby spots
Photo: Kentaro Ohno / Wikimedia Commons, CC BY 2.0 (resized)Shima OnsenGunma2 km away (straight line)- No photo yetHoshi OnsenGunma6 km away (straight line)
- No photo yetAgatsuma Gorge Rail Bike "A-Gattan!"Gunma15 km away (straight line)
Photo: 雷太 / Wikimedia Commons, CC BY 2.0 (resized)Chatsubomigoke Moss ParkGunma18 km away (straight line)
Photo: Aspere / Wikimedia Commons, CC0 (cropped and resized)Yubatake, Kusatsu OnsenGunma19 km away (straight line)
Distances are straight-line distances, not travel distances.
Crowds
- Crowd level
Not checked yet — no official source yet, and not enough traveler reports.
- Best time to visit
Not checked yet — no official source yet, and not enough traveler reports.
- Peak time
Not checked yet — no official source yet, and not enough traveler reports.
- Busiest days
Not checked yet — no official source yet, and not enough traveler reports.
- Busiest season
Not checked yet — no official source yet, and not enough traveler reports.
- Latest traveler report
- None yet
Traveler crowd data by time of day appears after 5 traveler reports (0 so far).
You can check typical busy hours in Google Maps ("Popular times" on the place's page). Open this spot in Google Maps
Verification log
- 27 Sept 2026First check · Tourism board · https://gunma-kanko.jp/spots/13Access, parking, description, address and coordinates read from a tourism organization's site.