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Oberhofen’s castle stands on the edge of Lake Thun, beside the boat landing. It gives the village a striking waterfront, but the park is just as good a reason to linger. You can spend a quiet part of the day among the trees and lakeside paths, then find somewhere for lunch.
A look inside the castle adds the museum to the visit. The park and museum have different opening dates and hours, so check the part you want to see. This is a garden to walk in, not a swimming or picnic spot.