It took the Colorado River millions of years to carve this nearly 300-mile long fissure in the earth. Considered one of the seven natural wonders of the world, it's hard to do justice to the Grand Canyon in words.
Five million people visit this hiking, rafting and backpacking mecca every year. Most leave with a renewed appreciation for wilderness and commitment to save it.
Toxic uranium mining remains the primary threat to this fabled region, though recent conservation victories offer new hope for its future.