In the Jungfrau region, there are actually quite a few unforgettable trains and cable cars up to high scenic viewpoints. But for most people, 2 of them compete for your attention, Jungfraujoch and Schilthorn. The Schilthorn takes you high above Mürren and offer better mountain views, but the Jungfraujoch gets you more into the mountains – quite literally – and I think it offers the more interesting and varied overall experience.
It’s a longish day to Switzerland’s highest train station. Grindelwald and Wengen are fairly close – but it can be easily done in a day. The cogwheel train, built at the turn of the century, actually tunnels through the Eiger for about 40 minutes, making 2 fascinating viewing stops to look out of rock windows high in the Eiger, before bringing you to the viewing complex near the top of the Jungfrau. Up here, you’re at 3,454 meters – over 11,000 ft – and it is always cold and chilly.
There are a ton of tourists and a variety of activities at the top, such as the ice palace where you can walk through a tunnel carved into the ice, but the main attraction is the view of the Aletsch glacier, the longest glacier in the Alps. I like the Jungfraujoch, but only on a sunny day and only if you have a generous budget, as the round-trip from the valley can cost upwards of $200 (it’s nice to have a Swiss rail pass for discounts). But it’s a great all-around experience. Go early in the day, as the weather often tends to cloud over as the day goes on, and you never know how long you might like to stay up at the top.