Sometimes called the Grand Canyon of Switzerland, the Rheinschlucht stretches over many kilometers from the town Castrisch nearly to the town Trin. It was formed several thousand years ago through a massive rockfall, which then got eroded by the river Rhine. Going by train to the. station Versam Safien takes you into the heart of the canyon. From there you can either hike to Flims, to Castrisch or to Trin. In every direction you will get to see a lot of amazing rock formations. If you feel trained enough then a hike from Castrisch all the way to Trin shows you the entire canyon. If you want to get good views from above, then just take the hike from Flims to the sightseeing platform called il Spir.