By 1925, millions of Americans owned cars. Prior to the rise of the automobile, most roads outside towns and cities were no more than improved wagon trails. Highways tended to be made of cobblestones and confined to major cities. Profit-making organizations formed to fund and build highways, but a lack of central organization resulted in chaos. By 1925, the US road network a hotchpotch of approximately 250 trails denoted by names, such as the Lincoln Highway, and sometimes through coloured bands on telegraph poles. The Federal government was under pressure to create a system of standardized highways and the Federal Highways Act was passed in 1925. A complete system of national highways, amounting to 96,626 miles (155,505 km) was approved, roads were to be numbered and road administration was turned over to individual states, which were to coordinate road building. The US was the first country in the world to introduce a numbered road network. For the most part north-south routes were given odd numbers, while east-west highways had even numbers.
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