San Xavier Mission - Tucson, Ariz.
San Xavier del Bac in Tucson was built from 1783 to 1797 after Father Eusebio Kino, a famous Jesuit priest, founded a mission on the site after his visit in 1692. Considered one of the finest examples of Spanish colonial architecture in the nation (and the oldest European structure in Arizona), the mission still houses much of its original statuary and paintings, and best of all, it's free to visitors.
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