51.   The steep canyon walls are frequently painted with dark splashes of algae where water seeps through the rock.

52.   The sun is already falling behind the red canyon walls above us.

53.   The water swept the canyon walls smooth, blanketed the sandstone with mud.

54.   Their homes are scattered throughout the canyons of Chihuahua, and their centuries-old footpaths can be seen across ridges and sides of canyon walls.

55.   Their findings, coupled with laser-mapping techniques and eventual borings from the canyon walls, will help determine the best spot to anchor the bridge.

56.   There are wide places chiseled from the canyon walls where two vehicles can squeeze past each other, which we had to do only a few times.

57.   They were up against steep canyon walls on one side, which reflected the heat.

58.   Twenty-five miles east of Caribou, the canyon walls receded in favor of rolling forest terrain.

59.   Waterfalls sluice sheer canyon walls.

60.   We watch as the rising sun paints the canyon walls a copper shade, which is reflected on the clear, slightly greenish water.