Just in case you live in Europe and Yosemite is too expensive and too far away for you, don't worry. There is a similar valley in Switzerland. It's called "Lautbrunnental".
It has its name from the 72(!) waterfalls in the area. A beautiful place in the middle of Europe/Switzerland.
Oh, and by the way, it was the inspiration for "Rivendell" in Lord of the Rings. Tolkien hiked often in this area.