major arterial divided highway that features two or more traffic lanes in each direction, with opposing traffic separated by a median strip; elimination of grade crossings; controlled entries and exits; and advanced designs eliminating steep grades, sharp curves, and other hazards and inconveniences to driving. Frequently expressways have been constructed over completely new routes, passing near but not through large centres of population, on more or less direct lines between desired termini. Their advantages include high speed, greater safety, comfort and convenience for drivers and passengers, and lower vehicle operating costs. Many of these new express highways, especially in the United States, are toll roads, but that is an incidental, not an essential, feature.
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