Dirt track racing began in the United States before World War I, drawing partly on the infrastructure of horse-racing tracks, whose banked oval layouts translated naturally to automobiles. The sport became widespread during the 1920s and 1930s. As dedicated speedways were built, the discipline evolved to host multiple vehicle categories under a single organisation's banner, and hundreds of local and regional racetracks proliferated across the country. The sport also reached Japan during the same early period, often using horse-racing venues.
A dirt track racing surface may be composed of any soil, though most experienced competitors regard a moist, properly prepared clay oval as the ideal surface. Track preparation is an intensive process requiring hours of skilled work. Equipment used typically includes a grader, a cultivator or rototiller, two types of rollers, and a watering truck. After an event the rutted surface is first graded smooth, then aerated with a cultivator to loosen the compacted upper layer and assist water penetration. Watering is repeated according to climate, location, and soil composition, with a final light watering before wheel-packing on race day. Outdoor tracks are typically aerated to a depth of 12 inches.
In North America, nearly all dirt ovals are less than 1 mile (1.6 km) in length, with the most common increments being one-half mile (800 m), three-eighths mile (600 m), one-third mile (540 m), one-quarter mile (400 m), and one-eighth mile (200 m). Longer tracks allow speeds up to 160 mph (260 km/h) with greater spacing between competitors; shorter tracks produce tighter, more physical racing with a higher incidence of contact.
In Great Britain, oval tracks are normally grass-surfaced with lengths of 400 to 800 metres. In mainland Europe, long tracks can be grass, sand, or cinder, and may extend to 1 kilometre in length.
Open-wheel cars on dirt ovals are purpose-built with tubular frames and unenclosed wheels. Classes range from the largest and most powerful sprint cars down through midgets and micro sprints:
Winged sprint cars use 410-cubic-inch, 360-cubic-inch, or 305-cubic-inch engines and carry a large top-mounted wing that provides aerodynamic downforce critical for traction and cornering. Non-winged sprint cars run the same basic machinery without wings, demanding greater mechanical-grip driving technique. The Silver Crown class fields larger, heavier cars on longer paved or dirt ovals. Midget cars and three-quarter (TQ) midgets are smaller, four-cylinder-powered variants. Quarter midgets are junior entry-level cars. Micro sprints and mini sprints bridge the gap between karting and full sprint car competition.
Open-wheel dirt racing is sanctioned nationally by the United States Automobile Club (USAC), the World of Outlaws Sprint Cars series (410ci winged), the All Star Circuit of Champions (winged, upper Midwest and mid-Atlantic), the High Limit Sprint Car Series (winged), and the American Sprint Car Series (ASCS, 360ci winged). POWRi administers midget and mini sprint competition.
Popular chassis manufacturers for winged sprint cars include Eagle, Maxim, J&J, Triple X, and GF1. Leading engine builders include Speedway, Kistler, Gaerte, Wesmar, Shaver, Don Ott Racing Engines, and Fisher Racing Engines.
Modified cars are a hybrid class with the rear wheels covered by fenders but open front wheels. They share some handling characteristics with stock cars but retain the directness of open-wheel oval machinery. Sanctioning bodies for modifieds include the Super DIRTcar Series, IMCA (International Motor Contest Association), UMP (United Midwestern Promoters), USRA (United States Racing Association), USMTS (United States Modified Touring Series), and WISSOTA.
Full-bodied stock cars on dirt ovals range from late models with full tube frames and aluminium bodies to lightly modified production vehicles. Classes at most dirt tracks include late models, super stocks, street stocks, and pure stocks, with rules governing permitted modifications calibrated to control costs and widen participation.
Dirt track racing in Australia has a history dating to the 1920s and 1930s, evolving in close parallel with the American tradition. Australian oval speedways host sprint cars, speedcars (midgets), and sedan classes. Most tracks are approximately one-quarter to one-third mile (400 to 540 m) in length. The predominant surface is clay, though some venues use dolomite, dolomite-clay mixes, or sand-clay mixes. A small number of tracks were paved with asphalt during the 1970s and early 1980s, but all eventually reverted to dirt.
Dirt oval track racing has produced a disproportionate share of the United States' most celebrated racing drivers and contributed foundational techniques — such as the controlled oversteer slide used to maximise corner speed on loose surfaces — that influenced driving styles across multiple disciplines including IndyCar and NASCAR. The sport continues as one of the largest participation motorsport categories in North America by number of competing venues and licensed drivers.