A ravine is a narrow, steep-sided landform created primarily by the action of flowing water and surface runoff. Technically a type of small valley, it is generally narrower and less extensive than a canyon but larger than a gully. For a concise definition see landform entry.

Characteristics

  • Shape and scale: Ravines typically have V-shaped or incised profiles with steep sides and a pronounced channel at the base.
  • Slope: Slopes are commonly sharp; many sources describe typical gradients as relatively steep, often cited in ranges such as 20–70% depending on local geology and climate. See further notes on slope measurement at gradient resources.
  • Hydrology: Some ravines carry perennial or intermittent streams that concentrate runoff, while others hold only ephemeral flow after storms. Compare their size with a canyon, which is usually much larger and deeper.
  • Vegetation and microclimate: Sheltered ravine floors can support distinct plant communities and cooler, moister conditions than adjacent uplands.

Formation and development

Ravines form when running water erodes soil and bedrock, cutting downward and headward into the landscape. Processes involved include stream incision, surface erosion during heavy rainfall, and occasional mass wasting of unstable banks. Human activities such as deforestation and concentrated runoff can accelerate ravine formation. General erosion mechanisms are discussed in more detail at erosion studies.

Ecology, uses and hazards

Because they channel water and often preserve undisturbed vegetation, ravines are important wildlife corridors and refuges for plants. They may be used for trails, scenic features, or local drainage, but they also pose hazards: rapid flooding, bank collapse, and accelerated soil loss are common concerns. Information on ravine streams and flood risk is available via stream and watershed resources.

Regional names and related forms include gullies, kloofs, coulees and glens; distinctions are largely matters of scale, geology and local terminology. Understanding ravines helps in land management, conservation planning and assessing erosion risk.