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Mesa Verde National Park, Colorado -- Return
15. Cliff Dwellings - From Douglas' record of tree-ring chronology, it was known that a great drought commenced in 1276 and extended for a 23-year period to 1299. |
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Mesa Verde National Park, Colorado -- Return
15. Cliff Dwellings - From Douglas' record of tree-ring chronology, it was known that a great drought commenced in 1276 and extended for a 23-year period to 1299. |
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