Ruins of the Library of Celsus in Ephesus, a former Greek city in modern Turkey. The city was important culturally and economically; it was home to the Temple of Artemis, one of the 7 Wonders of the World (and now a World Heritage Site), but it declined rapidly when the river filled the harbor with silt. Commerce moved a few miles away to Selçuk. Today Ephesus is a popular site for Christian tourism, easy to get to by airport or ferry. (Benh Lieu Song)