The Grand Canyon, including its extensive system of tributary canyons, is valued for its combination of size, depth, and exposed layers of colorful rocks dating back to Precambrian times. The canyon itself was created by the incision of the Colorado River and its tributaries after the Colorado Plateau was uplifted, causing the Colorado River system to develop along its present path. With unique combinations of geologic color and erosional forms decorate a canyon that is 277 river miles (446km) long, up to 18 miles (29km) wide, and a mile (1.6km) deep. Grand Canyon overwhelms our senses through its immense size.