Yosemite National Park has so many amazing waterfalls, that not all of them are strongly advertised. You might be able to find a few of them on a map, and The Cascades might be on one of them, but I can’t find it on a map now! With Yosemite Falls, Bridalveil Falls, and many others, it’s easy to forget the other amazing waterfalls!
I think you’ve officially entered the park by the time you see The Cascades, but I don’t believe you’ve entered the main loop. And that may be why it can be easy to miss. You may not see The Cascades depending on the direction you’ve come. I had tried to enter via CA-120 (headed south), but discovered that there was still snow falling in May. So I turned around, and connected onto CA-140, which heads into the park, and is open more. From 140, it’s almost impossible to miss The Cascades, unless you’re overwhelmed by some other breathtaking view. Still, it’s pretty hard to miss.
The total waterfall is 500′ tall (approximately), though I’m not sure about the height of the portion that is most visible. I have seen other pictures of the whole falls, but to me, it actually seems less impressive in the whole. Focusing just on the last drop, it seems to be very similar to the lower portion of Yosemite Falls. In May 2011, the flow over the falls was intense, which made stopping worthwhile. Another waterfall, Wildcat Falls, is very close by.
1) Head east along CA-140, entering into Yosemite National Park. You will have passed the pay station already.
2) A little less than 2 miles from the CA-140/CA-120 junction, you’ll find the parking pull-off for the falls. I didn’t have any difficulty finding a spot. (Use the junction as a guide. If you’ve passed the junction and you’re headed further into the park, you can turn around to find the falls. You could just try and see the falls on the way out, unless you’re taking a different route.)
Where in the World is the Cascades?: map