The Grand Canyon is unique in so many ways, it's difficult to know where to begin. It is home to arid deserts, pine forests, a major river, desert oases, unique wildlife, absolutely phenomenal geologic history, wonderful Native American history and remnants, 19th century mining and tourism history, and stunning scenery. There's really no where else like it on Planet Earth.
One of the most dramatic aspects to the Grand Canyon, and one that is extremely visible no matter where you go, is the geology. In Grand Canyon, the Colorado River has carved out a slice of the earth's history that goes back over 2 billion years! In the Inner Gorge, near the Colorado, is some of the oldest exposed rock on the planet, which was formed far before life existed at all here. Above that, ancient oceans, seas, sand dunes, and shifting tectonic plates have layered strata after strata of diverse types of rock from sandstone to shale to limestone and more. Some of the rocks are softer and create plateaus, some are very hard and create sheer cliffs. As you peer down into the Canyon or hike down one of the trails, seeing, understanding and appreciating these layers is one of the most entertaining and exciting aspects of the Grand Canyon.