Scenic Vistas: Grand Canyon, Arizona.A no-brainer. About 17 million years ago, the Colorado River began cutting its channels. Today, gaze upon a 277 mile long, 18 mile wide, 1 mile deep natural wonder. Seriously, you just cannot get a sense of its grandeur from a photo. Havasu Falls, within the Canyon, is a bonus attraction; its unusual blue-green color (from the magnesium in the water) has made it a favorite image on calendars.