Is it even worth trying to make photographs at any of the National Parks? Think of all those who have been there before you. How many have already visited, cameras in hand?
Just because others - many others - have worked a location doesn't mean you can't create something unique there.
Has every good book already been written? Has every story already been told? I don't think so. Common literary devices are utilized over and over, yet there's always a new twist. Different characters. An alternate perspective.
The same holds true with photography.
It might be more of a challenge to work in an "overphotographed" location, but that doesn't mean you can't make something special.
Freeman Patterson said, "The camera always points both ways. In expressing the subject, you also express yourself."
The more you allow yourself to get to know your subject and to connect with it...if you are patient...if you remain open to possibilities...if you're willing to explore...you can make images that are uniquely yours, no matter where you're shooting. And don't forget: no location looks exactly the same from one day to the next.

The image above exemplifies what's possible to create in a place that is "well-visited." I typically avoid the Moulton Barns in Grand Teton National Park because they're so often photographed. That doesn't mean I won't shoot them; but if I do end up there, it's because there's an opportunity to do something special.
On this day, I had been chasing storms from one end of the park to the other with little to show for it. Rather than continue to try to second guess the weather, I finally decided to stay put on the southern end. The only thing I could think of to use for potential foreground interest there were the buildings around Mormon Row. Somewhat reluctantly, I ended up at here at the T.A. Moulton homestead.
Because rain had been moving through, there were very few tourists present on this late afternoon. Long story short, I ended up capturing not one, but two spectacular storms at this location from opposite directions. This photo, with storm clouds violently swirling above the barn, was my favorite. It's most certainly not a "postcard shot" - which proves the point that you can do something quite unique at a place where countless photographs have already been made.