The total number of people fleeing the conflict in Syria has topped four million and shows no sign of stopping. The numbers, released by the UN, come as the conflict closes out its fourth year. “This is the biggest refugee population from a single conflict in a generation,” said the UN’s high commissioner for refugees. While some of the refugees make it to Europe and other countries outside the Middle East, the vast majority stays in neighboring countries. Nearly two million Syrians have spilled into Turkey, and more than a million are sheltering in Lebanon.