Ruts

Ruts are grooves worn into the ground by repeated passage of wheels, hooves, or tracks. They occur in natural soils as well as on roads and other surfaces and vary in width, depth, and length according to traffic, soil strength, and moisture.

Formation occurs as loads abrade the surface through repeated use. Soft or saturated soils, freeze–thaw cycles, and high traffic intensity accelerate rut formation. As grooves deepen, they can alter drainage, concentrate water in the channel, and increase erosion around the edges.

Cart ruts are a characteristic type found in places such as Malta and Sardinia. These parallel grooves cut into rock or soil are widely believed to result from prehistoric wheeled transport or sleds, though their exact dating and purpose remain debated.

In modern civil engineering, rutting refers to permanent deformation of asphalt or concrete pavements under traffic loads. Rut depth degrades ride quality, reduces drainage, and can worsen water infiltration. Mitigation includes good subgrade preparation, appropriate materials, compaction, drainage, and timely maintenance.

Ruts also reflect historical patterns of movement and land use, serving as indicators in archaeology and road history.