Canyonlands National Park has 3 sections (or districts? I forget.) We only visited one of them. You need a Jeep to tour the backcountry in the other districts. It's hard to pull a 34' 5th wheel with a Jeep.
To get down into the canyons, there are several choices: (1) high-clearance, 4-wheel drive vehicles, (2) mountain bikes, (3) long hikes on trails described as "primitive, rugged and strenuous" and (4) by river. Of course, you have to have backcountry permits for all of the above. We stayed on on the rim.
The Green River Overlook was pretty impressive--
Buck Canyon Overlook was too.
We had to hike to the edge of the canyon to see the White Rim Overlook. The sign said it was a level walk. The map said it was a 25' elevation gain. You can't believe what you read--there were more ups and downs than just 25 feet!!! And don't even ask about the distance. The white rim is actually a layer of rock called White Rim Sandstone. My book says it's 6 levels of strata down from the top.
Grand View Overlook was just that. The Colorado winds through the canyon, way, way down below.
George was pretty annoyed, but didn't say anything to anyone but me. That's a good idea--helps both domestic and international relations at National Parks. Here's a view through the arch without other people.
More pictures of Canyonlands here: Canyonlands NP