I had planned to save the hike along the Aaschlucht for a rainy day, which indeed it did on my first day in Engelberg, but it is a beautiful and relatively short hike, which is well worth doing, no matter the weather. Indeed, on a hot summer day the foliage would provide some cover from the sun. The hike is about 15 km and leads from Engelberg to Grafenort along the roaring Aa. Along the way there are various (suspension) bridges to cross the river. I rather stupidly didn't take any photos of the suspension bridges, although I did take some photos while standing on one. From Grafenort you can take the train back to Engelberg. I recommend checking the timetable to avoid a long wait in Grafenort.

Aaschlucht Engelberg
The spectacular Aaschlucht in Engelberg
Aaschlucht Engelberg
It is worth carrying a tripod if you want to take nice waterfall photos, which I didn't do.
Looking down from one of the bridges
Aaschlucht Engelberg
The Aa is surrounded by a lush forest
The Aaschlucht is quite spectacular
The hike along or through the Aaschlucht was much more fun than I expected

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