Mission San Xavier del Bac
294-2624, off I-19 at exit 92. Free. 7 a.m.–5 p.m. Allow 2–3 hours.Once part of a chain of churches that stretched from northern Mexico to the western U.S. This brilliant white structure is considered the “Sistine Chapel of North America” for the intricate paintings on the walls and ceiling. It is still a Catholic parish serving the Tohono O’odham community for whom it was established in the late 1600s.