Day one is not a gentle spin out of town; it is a clear move from lake country into the mountains. From Interlaken the route runs to Bönigen and reaches Lake Brienz almost immediately. It stays on the southern shore: pale water on one side, forest, rock and the steep slopes above Iseltwald on the other. After the village the road climbs. Near Giessbach the lake is already lower below the road, the waterfalls drop through the trees, then the route descends towards Brienz. Meiringen marks the start of the Haslital: station, shops, bakeries, then Innertkirchen. From there the pass becomes the subject. The Aare follows the road, the valley narrows, and Guttannen is the last stop before the Grimsel.