Am wandering if anyone can suggest a route from st. louis to yellowstone national park, where we could see the most. I realize this is a long drive and wonder if it would be better to fly into Salt Lake City and rent a car. Any help sure would be apprecited.

It depends on how long you want to make the drive, really. I used to drive straight out to Denver and then choose some of the more scenic drives along the foothills up past the Tetons and into Yellowstone. But that drive from St. Louis to Denver, especially once you're past Topeka is not the most inspiring and you're right - it's very long.

Another way, if you're not in a time crunch, my be to head north into the Dakotas and see the Badlands and Rushmore and go across that way, through Montana.

If I were picking though now, I'd probably fly into SLC or Denver and drive up that way, so that I got to spend the maximum amount of time in the Rockies. Those kind of drives for me were better suited to the days when just the gas money was expense enough.

I think some of this may be repetitive.
The scenic route that will fit in with your limited travel time, unless it has changed from your earlier posts, would be to take the direct route to Denver, I 70. Go north to Casper and on to the east slope of the Bighorn Mountains. Go west over the Big Horns toward Yellowstone at either Buffalo, or north of Sheridan. If you turn at Buffalo, the route on the west takes you down the steep west escarpment via Ten Sleep Canyon. It is so steep that I had to stop and let my ears catch up with the air pressure change.

Either way lengthens the trip some.

If you want to include Rushmore, you could turn east just before
Casper and go via route US 85 and 18 to Rushmore. Or turn north on US 385 at Burlingon Co. One way backtracks a little; the other way zigs and zags and is non Interstate.

Either way, detouring by Rushmore cuts a day off your Yellowstone time.

I think you need to decided which destination gets priority and what your trip objectives really are.

If you fly, the drive up from Salt Lake City via Logan, Bear Lake, and the Snake River Gorge to Jackson is scenic, probably much more so than that long drive across flat Kansas and the eastern third of Colorado.

If you drive the route via Casper, once you turn west toward the Big Horns, the view gets more scenic west of Buffalo. But Wyoming between the Big Horns and Cody is dry and somewhat featureless. Things start to get more interesting as you approach Yellowstone from Cody.

If you want the most scenic entrance into Yellowstone, take the Chief Joseph Highway north from Cody and come into Yellowstone through the Northeast Gate.
Again, this route is longer and will delay you in getting to Yellowstone.
So with limited time, it boils down to priorities.

I really think you need a good regional map of the Rocky Mountain west so you can visualize the trip perhaps a little better. I get confused myself switching between state maps, and I have driven that route more than once.

From experience I can tell you that trying to cover more than 650 miles a day in a car for several consecutive days gets old quickly.

You are spending 11 to 12 hours in the car because you have to stop for gas and other purposes.

I have gotten to where I fly from Georgia to Salt Lake City or Denver depending on air fare because by the time I buy gas and pay for motels, I can fly for just a little more if the airfares are right. And I get more time at my destination.

Thanks again for your help. It all sounds so beautiful. I've taken the boys to Colorado last year, but imagine Yellowstone is no comparison. Thanks again for any other suggestions.