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A road circuit of Lake Thun takes you through Spiez, Thun, the north-shore villages and Interlaken. There are plenty of lakeside stops, but the full ride needs several hours plus breaks. For a gentler outing, ride just one stretch. This is a cycling circuit, separate from the lake’s long-distance walking trail.
Expect hills and stretches in road traffic. An e-bike helps on the climbs, but you still need to be confident riding among vehicles. Use the current cycle-route information to check road conditions and choose a bike suited to the surface.