An unpaved road is a type of road whose surface has not been sealed with a pavement treatment, [1] such as concrete or bitumen. An unpaved road can be a dirt road, whose surface is the native material of the land surface (known as subgrade material), or it could be a gravel road, where the subgrade material has been covered by gravel but not sealed. There are approximately 13 million km (8.1 million mi) of unpaved road in the world, making up 57% of the total road length. [2]
 | This section needs additional citations for verification .(January 2026) |
A forest road is a type of rudimentary access road, built by private companies, or government entities such as the United States Forest Service to access remote undeveloped areas. These roads are built mainly for the purposes of forest management, timber harvest, and livestock grazing, [3] although in some cases they are also used for backcountry recreation access.
Typically, a high-clearance four-wheel drive vehicle is required to travel effectively on a forest road, especially where large potholes and/or waterbars are present. Switchbacks are employed to make the road passable through steep terrain.
These roads rapidly fall into disrepair and quickly become impassable. Remnants of old roads can exist for decades. They are eventually erased by washout, erosion, and ecological succession.
For logging roads, the choice of road design standards is a tradeoff between construction costs and haul costs (which the road is designed to reduce). A road that serves only a few stands will be used by relatively few trucks over its lifetime and so it makes sense to save construction costs with a narrow, winding, unpaved road that adds to the time (and haul costs) of the few trips. A main haul road serving a large area, however, will be used by many trucks each day, and each trip will be shorter (saving time and money) if the road is straighter and wider, with a smoother surface.
Logging trucks are generally given right of way. In areas that the practice is regulated, on non-highway roads with heavy logging traffic may be "radio-controlled", meaning that a CB radio on board any vehicle on the road is advised for safety reasons.
According to the British Columbia Ministry of Forests, resource roads are typically "one- or two-lane gravel roads built for industrial purposes to access natural resources in remote areas". [4] They may be used by industrial vehicles or the general public, and as a link to rural communities. [4] Driving on resource roads can be hazardous for many reasons, including limited visibility, unusual road geometry, and the presence of wildlife. [4] Disused resource roads can pose a danger to both drivers and passersby, due to the danger of landslides forming on unstable, poorly-drained ground. [5]
A primitive road is a minor road system, used for travel or transportation that is generally not maintained or paved. [6] Primitive roads primarily occur in rural farmlands, deserts, or forests rather than in developed areas.
There is no universal definition of primitive road. According to Washington (state) law, an unpaved road is a primitive road if:
Road maintenance on primitive roads is optional for the county in Washington. [7]
While most gravel roads are all-weather roads and can be used by ordinary cars, dirt roads may only be passable by trucks or four-wheel drive vehicles, especially in wet weather, or on rocky or very sandy sections. It is as easy to become bogged in sand as it is in mud; a high clearance under the vehicle may be required for rocky sections.[ citation needed ]
Driving on unpaved roads presents hazards often not present on paved or sealed roads:
The CIA Worldbook provides an estimate of the total length of unpaved roads per country for most, but not all countries in the world. The top 10 countries with the largest amount of roads is shown in the table, below: [12]
| Rank | Country | Length of unpaved roads (km) |
|---|---|---|
| 1 | United States | 2,281,895 |
| 2 | Brazil | 1,754,000 |
| 3 | Australia | 727,645 |
| 4 | Canada | 626,700 |
| 5 | China | 622,000 |
| 6 | Mexico | 529,358 |
| 7 | South Africa | 591,876 |
| 8 | Sweden | 433,034 |
| 8 | Russia | 355,666 |
| 10 | Finland | 350,000 |
