Mission San Xavier del Bac is situated in the Sana Cruz Valley nine miles south of Tucson Arizona. Framed in the warm browns of the surrounding hills and the violet shadows of more distant mountains, it rises, brilliantly white from the desert floor of dusty green mesquite and sage. The imposing dome and lofty towers, the rounded parapets and graceful spires etched against the vivid blue complete a skyline fraught with a gracefull enchantment.