Lauterbrunnen: Part of Bernese Oberlands. Weather a bit chilly, but beautiful in May.
A valley in the midst of majestic mountains and 72 waterfalls. See some of Switzerland's most famous peaks: the Eiger, Monch & Jungfrau.
Walking, Hiking, Biking, Sightseeing, Skiing
Arrive by train at Interlaken OST. Buy ticket to Lauterbrunnen. (Not included in Eurail but discount ticket = 11.40 CHF)
Walk south from Lauterbrunnen on the road closest to the waterfalls. About 45 minutes walk to Trümmelbach and then another 30 to Stechelberg (plus picture-taking time.)
I walked one way then took the bus (4.40 CHF) back. Can also bring/rent bikes.
Stop at Trümmelbach & ride the lift deep into the mountain to see 10 hidden glacial waterfalls gushing around you. Cost: 11 CHF
Pack a picnic lunch to save some money!
Mürrin: the least expensive stop on the cable car at 22 CHF round trip. You'll get a good view of the Eiger, Monch & Jungfrau.
(For comparison, 102 CHF will get you even higher to Schilthorn where the James Bond film On Her Majesty's Secret Service was filmed and 184 CHF gets you to Jungfraujoch.)
Thanks to my sister and her native Swiss husband for the recommendation!