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Give Lauterbrunnen more than a photo stop beneath Staubbach Falls. Start in the village and follow the valley as far as you feel like walking. Trümmelbach is a different, paid visit farther along, with glacier water inside the mountain; check its season and access rules.
Wengen and Mürren are different directions. The railway climbs to Wengen; one route to Mürren uses Grütschalp and the train via Winteregg. Choose your village before following the next departure. You do not need a summit ticket to enjoy the valley. The accommodation on this site is around Lake Thun, not in Lauterbrunnen.