What would a city be without culture? No place we'd want to live. Yet most attempts to seed thriving centers are fraught with stumbles. The new AT&T Performing Arts Center solidifies Dallas's arts district by bringing a red-hot heart to the city's downtown, already home to a symphony hall and sculpture museum. The center, which opened in October and includes the Wyly Theatre and Winspear Opera House, attracted more than 100,000 visitors its first season. "It's not just the number of facilities but the nature of the facilities," says center CEO Mark Nerenhausen. "We've reached critical mass."