Probably best known from several commercials for cigarettes, Monument Valley is also one of the major attractions for every tourist. Although it's not my personal favorite, the freestanding limbstone formations are certainly an impressive sight.

To get there, you'll have to pay an entrance fee which is not covered in the Eagle Pass, which is normaly valid for every National Park in the states. Also, the campsite in the State Park is not really well maintained, so I wouldn't recommend spending the night there.
For me, the whole place looked rather like a commercial tourist trap, plus, I don't think it's worth to hike there, since you'll probably get no new views or impressions of Monument Valley.

Arches National Park / Bryce Canyon National Park / Canyonlands National Park / Capitol Reef National Park / Crater Lake National Park / Death Valley National Monument / Grand Canyon National Park / Lassen Volcanic National Park / Las Vegas / Lava Beds National Monument / Mesa Verde National Park / Monument Valley / Mount Rainier National Park / Olympic National Park / Petrified Forest National Park / Point Lobos State Park / San Francisco / Salt Lake City / Seattle / Sequoia National Park / Valley of Fire State Park / Yellowstone National Park / Yosemite National Park / Zion National Park