Grand Canyon National Park

Arizona, USA
This fabled natural wonder needs little introduction. The canyon, carved out by the Colorado River over millions of years, plunges a mile (1.6km) deep and stretches on for some 277 miles (446km). It's a picture of burnt red bluffs, broken up with bands of green, pink and orange. Lucky are the bighorn sheep, mountain lions and elk that call this rocky expanse home.