I just got back from my spring break trip, this year I rode the White Rim Road in Canyonlands National Park. Here is a link to pictures, I'm too lazy to link to all of them.
This road is a 100 mile ride along the aptly named White Rim, here is some info:
Park Service Info For The White Rim
It was an amazing ride. Pete, my officemate and I decided to do this ride self supported, Pete using his touring bike with panniers while I used the Surly with my BOB trailer attached. Things didn't start out that well, I had a problem with my skewer that is needed to connect the trailer and when I climbed into my new sleeping bag for the first time, I found that it had a large hole in it! Luckily, I bought it at REI and I'm sure I can get a new one without any hassle.
Anyways, we started Monday morning and managed to put about 50 miles down the first day. We both agreed that the ride would go faster with a mountain bike, simply because you could fly over the little bumps. The shaking gets to you after a while when you have no suspension. It was definitely doable though, and I think it was good practice for later this summer.
After a nice desert night, we finished the second 50 miles. This portion was significantly easier than the previous day, we had the wind at our backs but mainly the road was smoother and our skills much improved on the dirt allowing us to double our average speed from the previous day.
I really recommend this ride to anyone, its really beautiful and challenging! In a few days Pete and I will throw together a full travelogue with pictures, but I'm too lazy now to do it and he has more pictures.