Urban Neighborhoods, Once Distinct by Race and Class, Are Blurring

America’s cities have changed considerably over the past half century, in ways that challenge and confound our theories for understanding them.

Back in the early 20th century, the urban theorists associated with the Chicago School—Robert Park, Ernest Burgess, Homer Hoyt, and others—laid out the basic model which still shapes the way we think about cities. Cities are formed around a dense, commercial core. Surrounding that core is a warehousing, logistics, and food-servicing area: neighborhoods like New York’s Chelsea, Meatpacking District, Soho, and Tribeca, which are now rife with gentrification. As you move further out, dense multifamily housing areas eventually give way to suburban residential districts with lower and lower densities, filled with more affluent residents living in greener and tonier neighborhoods.