Over the nation's first 150 years, most towns, cities and early suburbs grew along fairly rigid grids where the topography permitted it. Smaller avenues crossed one or more long, main streets. This made access to and among all the streets fairly fluid.
It also made for a lot of traffic, noise and accidents at intersections. So new, planned housing subdivisions, which appeared with the return of millions of servicemen and women from World War II in the 1940s, followed quite a different model. There were still big, central streets - often wide boulevards. But branching off were nodules called cul-de-sacs, or streets that dead-ended into little traffic circles.
In French, cul-de-sac means "bottom of the sack." And as in that sack, there's no exit at the end of a concrete cul-de-sac. Thus, no reason to speed to a big cross-street up ahead. That was a huge selling point to homebuyers, who sometimes paid a premium for houses on cul-de-sacs. Their children could play safely right in the street, and strange cars were far more noticeable than on the typical city street. "Crooks look for multiple exits," a homebuilder association executive told the Washington Post.
Subdivisions and cul-de-sacs multiplied like rabbits across the land. But not so much any more. The State of Virginia, for instance, has decreed that streets in future subdivisions must connect to main arteries and other neighborhoods. Why? Because cul-de-sacs are hard for emergency vehicles like fire trucks to reach quickly, and once they're there, turning around is difficult. Dead-end streets are also more challenging and expensive to clean and plow. Cutting down on cul-de-sacs will bring back more cross-streets, giving drivers alternate routes when main streets are jammed.
Some other states say they, too, will require more access to future subdivisions. The cul-de-sac will endure, most likely, at least in neighborhoods where the residents have enough political clout to insist upon it.
boulevard: a broad avenue in a city, usually having areas at the sides or center for trees, grass, or flowers（林荫大道）
cul-de-sac：a street, lane, etc., closed at one end; blind alley; dead-end street（死胡同）