After spending his first full day in the grandeur of Mexico City's historic center, Francis is heading to the capital's periphery for a Mass on Sunday in Ecatepec, a sprawling suburb of 1.6 million where drug cartels hold sway and the murder rate, especially for women, is particularly high. Pilgrims sporting white baseball caps wrapped themselves in blankets to guard against temperatures that dipped in to the 30s Fahrenheit (about 3 celsius) as they trudged along the roads leading to the Mass site, a sprawling field that has a capacity of 400,000 people.