For my visit into Canyonlands, I traveled into the "Island in the sky" region. Canyonlands is the most isolated and rugged NP in the lower 48, and access by vehicle is extremely limited. Island is the most easily accessable, with the most features off of paved road.
I had actually traveled one of the gravel roads out of Moab to under the rim of Island, and I will post details of that visit in another posting. The pictures of the gravel road squirreling up from below is what I would have come in on if I had continued that trek. While my toybox thinks it is invincible and can travel on anything, I don't always fall for that, and luckily had turned around well beforehand :).
The views from here were absoutely incredible. I doubt that any of my pics capture the true essence of the raw beauty of the canyons, and if you'd like to see better ones, visit the photo gallery http://www.nps.gov/cany/photosmultimedia/index.htm
At Mesa arch, I offered to take some pics of a group standing on top of the arch, and they offered to do likewise for me. One, it is posted not to climb it, but really, it was a long ways down from the backside ;'). A very nice spot none the less.
I finally know the difference between Mesas and Buttes from this visit. Only took me more than a month to find this out... A mesa is wider than tall and a butte is taller than wide... aw, makes sense.
Upheavel dome is a mystery to science. It could be a crater from a meteorite or a salt dome. Whichever, it is an impressive sight, some 3 miles across with a formation jutting up out of the middle...
Once I reached Green river and grand view points, I was consumed for the rest of the day, taking in the massiveness and intricicies of maze of canyons below, along with the mesas and buttes. This is truly erosion at its finest!