But even by the 1920s it was becoming controversial, as urban congestion and traffic accidents mounted.

ECONOMIST: A Survey of the 20th Century

The reduction in urban traffic also depends on the successful introduction of urban-congestion charges and taxes on workplace parking.

ECONOMIST: British election briefing: Transport

The county council said the route will reduce traffic congestion and support Lincoln's growth as a principal urban centre.

BBC: Lincoln east-west route plans on display

One study estimated that traffic congestion wasted 4.8 billion hours and 1.9 billion gallons of fuel a year for urban Americans.

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