READERS' PICK: This profoundly Sonoran celebration commemorates the feast of San Francisco Xavier, patron of the mission. He's the guy you'll see reclining in the west transept of the church most of the year, his beautiful wooden head rubbed smooth by centuries of loving hands, his gown covered with photos and milagros and little locks of hair. On the night of the fiesta he's brought out into the center of the church and hundreds of faithful come to pay their respects. Pascolas and a deer dancer perform at the big old doors, and outside the church the air is thick with mesquite smoke and the smell of popovers, the O'odham version of frybread. After dark there are fireworks. Do it right and join the pilgrims who've made a manda to walk from their homes to the mission that day.