Image source: Flickr CC user Allie_Caulfield When the history of 20th-century urban development is written, one of the hidden key factors will be the development of shopping malls. Though they are now often reduced to kitsch and mocked as sterile, malls had a dramatic impact on cities and inner suburbs starting in the 1970s (not to mention the economically positive impact they had on the the often barren areas where they were built). Suddenly, there was a space where businesses could go that had hundreds or even thousands of free parking spaces. Stores left downtowns and main streets for less-expensive rent and easy access by consumers. Many municipalities took decades to recover, if they ever did at all.