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Mesa Verde National Park, Colorado -- Return
14. Cliff Dwellings - The tree-ring specimens which yielded the dates of several of the park ruins had been collected by the National Geographic Beam Expedition of 1923. |
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Mesa Verde National Park, Colorado -- Return
14. Cliff Dwellings - The tree-ring specimens which yielded the dates of several of the park ruins had been collected by the National Geographic Beam Expedition of 1923. |
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