Grand Canyon Trail of Time 20100911mq_6404a

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Size: 1986px × 2516px
Photo credit: © NPS / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: canyon, earth, education, eons, geology, grand, grandcanyon, hike, history, national, natural, nps, park, rocks, science, service, time-line, timeline, trail, walking