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A lawn, a towel and a swim can be enough of a summer plan. Spiez’s lido and Thun’s Strämu combine pools with lake access, which gives families more choice than searching for an unnamed cove. They are paid, seasonal facilities; an open park in winter does not mean its pools are operating.
For any natural-water swim, check permitted access, conditions and your own ability before entering. The lake is different from a pool, with colder water and changing weather. A quiet-looking shore is not evidence that it is safe, public or supervised. Keep children close and follow local signs.