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A gravel road is a type of unpaved road surfaced with gravel that has been brought to the site from a quarry. They are common in lesser-developed nations, and also in the rural areas of developed nations such as Canada and the United States. In New Zealand, they are known as 'metal roads'.^[1]

Contents 1 Characteristics 1.1 Construction 1.2 Maintenance 1.3 Driving 2 References 3 See also 4 External links

Gravel roads are comparatively easy to build, as they only require the equipment and material to provide a base course of hard-packed earth or other material, covered with one or more different layers of gravel. Most other road building requires large machinery to work and pour concrete or to lay and smooth a bitumen-based surface. Therefore, gravel roads are easy to build where suitable material is available, and cheap to build with manual labour (though some kind of grading equipment is usually required). Even in developed nations, the building costs are far below a sealed road.

Gravel roads however do require much more frequent maintenance than paved roads, especially when (suddenly) faced with increased traffic. The wheel motion shoves material to the outside (as well as in-between travelled lanes), leading to rutting, reduced water-runoff and eventual road destruction if unchecked. As long as the process is interrupted early enough, simple re-grading is sufficient, with material being pushed back into shape.

Gravel roads are also often found in areas with cold climates because they are less vulnerable to freeze / thaw damage than asphalt roads and also because the inferior surface of gravel is not an issue if the road is covered by snow and ice for extended periods anyway.

Even good gravel roads are limited in terms of their suitability for high speeds. An associated problem is the possibility of stones skipping and hitting the car body or windshields, especially when two vehicles pass each other.

• Trail

• Gravel Roads Maintenance and Design Manual

v • d • e Types of road
High-speed access via interchanges	Autobahn • Autopista • Autoroute • Autostrada • Auto-estrada • Freeway • Lebuhraya • Motorway
High-speed other types of access	2+1 road • Divided highway • Expressway • Farm to Market Road • Highway • Parkway • Super two
Low speed	Arterial road • Boulevard • Frontage road • Road • Street
Low speed low traffic	Alley • Cul-de-sac • Driveway • Lane
Other	Dual carriageway • Interchange • Range road • Roundabout • Toll road
Surface types	Asphalt concrete • Brick • Cobblestone • Concrete • Corduroy road • Dirt road • Gravel road • Ice road • Macadam • Oiled road • Plank road • Tarmac • Winter road