Egyptian worshipers perform take part in an evening prayer "Taraweeh", at Amr Ibn al-Aas mosque, in Cairo on May 30, 2017. Ramadan is sacred to Muslims because it is during that month that tradition says the Koran was revealed to the Prophet Mohammed. The fast is one of the five main religious obligations under Islam. More than 1.5 billion Muslims around the world will mark the month, during which believers abstain from eating, drinking, smoking and having sex from dawn until sunset. Photo by Amr Sayed