You can travel by train between Lauterbrunnen and Grindelwald. But it is not a direct train.

In both directions, you change trains at the Zweilütschinen stop. Here's how to do it.

From Grindelwald to Lauterbrunnen

1. From either the Grindelwald or Grindelwald Terminal station, get on the train headed to Interlaken. It departs every 30 mins.

2. Ride to the Zweilütschinen stop.

3. Exit the train and wait 8 mins, waiting in section AB labeled Lauterbrunnen.

4. When the train from Interlaken arrives, board the train, making sure you are on the Lauterbrunnnen part of the train. The train will split and the back half of the train goes to Grindelwald.

From Lauterbrunnen to Grindelwald

1. From Lauterbrunnen, get on the train headed to Interlaken. It departs every 30 mins.

2. Ride to the Zweilütschinen stop. Exit the train and wait 8 mins, waiting in section CD labeled Grindelwald.

3. When the train from Interlaken arrives, board the train, making sure you are on the Grindelwald part of the train. The train will split and the front half of the train goes to Lauterbrunnen.