But for the Iraqi travelers, almost all Shi'ites, the trip isn’t just a religious pilgrimage. Their three-month visas give them a respite from the dangers of Iraq, where violence between Sunni and Shi’ite Muslims had made daily life stressful and frightening. In Iran, a country that’s more than 90 percent Shi’ite, and tightly controlled by a government of Shi’ite clerics, they don’t have to worry about sectarian killings.