The Swiss Travel Pass offers excellent coverage in the Jungfrau region, but it works differently for different routes. All trains between Interlaken Ost, Lauterbrunnen, and Grindelwald are 100% covered (free). From Lauterbrunnen and Grindelwald up to Wengen and Mürren, the pass is also fully valid. For the more "excursion-style" mountain railways, such as the famous trip to the Jungfraujoch (Top of Europe), the pass acts as a discount card rather than a full ticket; it covers the journey from Interlaken to Grindelwald/Wengen, but you receive a 25% discount on the final cogwheel train from Kleine Scheidegg to the summit. Similarly, for the Schynige Platte and Harder Kulm, the pass provides a 50% discount. While the pass is very generous, visitors should check the specific "Area of Validity" map, as the Jungfrau region has many privately owned cable cars that may require a separate ticket, albeit at a reduced price for pass holders.