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The economic purpose of the Chaco road system is shown by the presence of luxury items at Pueblo Bonito and elsewhere in the canyon.
Items such as macaws, turquoise, marine shells, and imported vessels prove the long-distance commercial relations Chaco had with other regions.
A further suggestion is that the widespread use of timber in Chacoan constructions — a resource not locally available — needed a large and easy transportation system.
Through analysis of various strontium isotopes, archaeologists have realized that much of the timber that composes Chacoan construction came from a number of distant mountain ranges, indicative also of the Chaco Road's economic significance.

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