Ever since the first European settlers arrived, North America's town founders and planners have asked some big questions about how to shape the places we live.
What if we arrange our homes and businesses around an orderly grid of streets? What if we build a company town with housing for all of our workers? What if we lay out a town to provide people with more green space? What if we build homes ultra-efficiently, the way Henry Ford built cars? What if we tear down old neighborhoods to build new ones? What if we don't?
The pursuit of these "what ifs" has led to some great experiments in urban planning, with results that have impacted many other places-for better and occasionally for worse.