[91, Library of Celsus, AD 110–135, Ephesus, Turkey] The ancient city of Ephesus (on the west coast of today's Turkey) was Greek before it became Roman — a good example of cultural Romanization. Its main street, once lined with fine buildings, leads past a striking temple dedicated to the Greek-loving Roman Emperor Hadrian. And the city's library — filled with books in both Latin and Greek — showed off the Romans' cosmopolitan flair. This striking façade — featuring statues of women who symbolize the virtues of learning and wisdom — inspired the citizenry.

[92, Roman theater, first century AD, Ephesus, Turkey] Like any great Roman city, Ephesus had a fine theater. With good acoustics designed into the semi-circular seating and the sound wall behind the stage, huge gatherings could enjoy the plays and events here with unamplified voices. Its acoustics, remarkable back then, remain so to this day.

[93] To estimate an ancient city's population, archaeologists consider the capacity of its theater. Ephesus was big; it needed a theater that could seat 25,000. And imagine: it was just one city in the vast Roman Empire.