Encouraged by social media, approximately 50,000 people crossed into the Spanish enclave of Ceuta from Morocco starting Thursday, July 30th, creating an unprecedented influx. This mass movement appears to have been spurred by online messaging. However, the vast majority of those who entered Ceuta have already been forced to return to Morocco. The situation represents a significant, though short-lived, migration event. Authorities are now assessing the circumstances surrounding the sudden surge of people. The incident highlights the power of social media in rapidly mobilizing populations. Many of those involved described the attempt as a once-in-a-lifetime opportunity, now lost.