Since around 4000 BC, humans have settled in Aqaba, Jordan's only seaport city, located on the northern banks of the Red Sea. Now it is a major tourist attraction because of its beach resorts and luxury hotels. But Aqaba's history is even more impressive. In 1998, archaeologists found what is believed to be one of the world's oldest Christian churches, said to have been built in the 280 A.D. (CHRIS RENNIE—GETTY IMAGES)