In 1879, when the ____________ reached New Mexico, people stopped using the Santa Fe Trail.
Explanation:
<u>The Santa Fe Trail</u> <em><u>was opened in 1821 by merchant William Becknell</u></em>, <u>and was used until the arrival of the railroad in 1879-1880</u>.
<em><u>The answer is</u></em>: <u>For the arrival of the railroad.
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