Santa Fe, New Mexico, is the US state capital that has the highest percentage of dirt roads — about 75%. By comparison, about 35% of all roads in the US are not paved. The city of Santa Fe contains about 574 miles (923.76 km) of roads, and about 430 of those miles (692.02 km) are not paved. Dirt roads tend to be cheaper to maintain than paved roads, but they can be more dangerous at high speeds because they are more prone to holes and ruts. Dirt roads also produce dust and other debris that can be propelled into the air by moving vehicles.
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