
Lake Haruna
A caldera lake at 1,084 metres on the volcano Mt Haruna. The lake is famous for its winter ice fishing (smelt) when the surface freezes solid enough to walk on, its summer wakasagi fishing from boats, and the horse-drawn sleighs that cross the frozen surface in February.
Half day
Free (fishing permit ¥700)
Always open; boating and fishing: Apr–Nov; ice fishing: Jan–Feb
January–February (ice fishing), June–September (summer)
Bus from Takasaki Station (JR Joetsu Shinkansen, 60 min)
Location
Why Visit
- 1
In winter, the frozen lake surface is thick enough for ice fishing tents and horse-drawn sleighs
- 2
Ice fishing for wakasagi (smelt) is open to anyone with a rental rod — over 1,000 fish per session is common
- 3
Mt Haruna's summit ring of peaks creates a wind-protected caldera — snow piles 2m+ without blowing away
Local Tips
Lake Haruna sits in a volcanic caldera at 1,084m — the surrounding hills and Mt Haruna reflected in the water are picturesque year-round. Row boats and pedal boats available Apr–Nov. In summer the lake is 5–8°C cooler than Takasaki city below — a genuine escape. Combine with Ikaho Onsen (30 min by bus) for a full Gunma mountain day.
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