Grand Canyon National Park in Arizona is one of the most natural wonders of the world. It is a mile deep (1,500 meters) and over 15 miles (20 km) wide by 100 miles (150 km) long.
The interior of the Canyon is adorned with a vast maze of colorful mesas, cliffs and promontories punctuated by a labyrinth of smaller canyons and gorges. The ever-changing play of sun and shadow on the multihued rock layers produces a breathtaking display best seen from the visitor's center on the south rim. The only access to the interior of the canyon is by hiking or by riding mules down the precipitous trails.