Milan’s famed opera house is cracking down on the underdressed, even as it and other European opera companies try to attract a wider audience. By Amelia Nierenberg This was featured in live coverage.

Thirty-five years ago, I visited Vienna on my first backpacking trip to Europe. I have a faint memory of touring the Kunsthistorisches Museum, Naturhistorisches Museum, Schönbrunn Palace, and ...