The gondola to get to Grindelwald takes about 30 minutes. At the top is the cliff walk which is a crazy high and frankly, kind of scary walk. Takes about 15 minutes to walk this. There are a couple of other things to do at the other stops along the gondola (Trottbikes @ Bort, First Glider @Schreckfeld). Along with the cliff walk, there are numerous other hikes to do at the top of Grindelwald. But I’m glad we spent majority of our time in Lauterbrunnen.