What was the spaniard vázquez de coronado’s main achievement as an explorer?

The 16th-century Spanish explorer Francisco Vázquez de Coronado (c. 1510-1554) was serving as governor of an important province in New Spain (Mexico) when he heard reports of the so-called Seven Golden Cities located to the north. In 1540, Coronado led a major Spanish expedition up Mexico’s western coast and into the region that is now the southwestern United States. Though the explorers found none of the storied treasure, they did discover the Grand Canyon and other major physical landmarks of the region, and clashed violently with local Indians. With his expedition labeled a failure by Spanish colonial authorities, Coronado returned to Mexico, where he died in 1554.
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The led the formation to the united states