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A calm morning on Lake Thun is a good time for a paddle close to shore. Hire a canoe or SUP and ask the rental team for a short route that suits the wind that day. Boat traffic and a rising wind can make the return harder than the outward paddle.
Prefer to go with a guide? Hightide runs kayaking trips from Bönigen on Lake Brienz. The operator lists dates and participation requirements. Winter kayaking is a separate outing with different clothing and preparation; summer SUP hire has its own season.