mountainvalley

Mountain valley is the geographic term for a long, low area that lies between mountains. These valleys typically form where rivers erode between ranges or where glaciers carve the landscape, though many valleys experience a combination of processes. In river valleys, downward erosion produces V-shaped profiles; later sediment deposition and stream meanders can create broader floors. Glacial valleys often take a U-shaped cross-section with steep sides and flat bottoms. Tectonic uplift and rock structure also shape valley geometry and drainage patterns.

Valleys host streams or rivers that drain toward downstream basins, creating microclimates and diverse habitats. Valley floors commonly accumulate fertile alluvial soils, supporting agriculture, forests, and human settlements along rivers and passes. The climate inside a mountain valley varies with elevation, aspect, and exposure, creating vertical zoning of ecosystems.

People have inhabited and utilized mountain valleys for transport, settlement, and recreation. Roads, railways, and tunnels frequently traverse valley floors or headwalls. The valleys also attract tourism for scenery, hiking, skiing, and mountaineering.

Hazards include landslides, rockfalls, avalanches, and floods, particularly after rapid snowmelt or heavy rain. Slope stability, drainage management, and land-use planning help mitigate risks.

Examples include Yosemite Valley in California, Engadin in Switzerland, and numerous alpine valleys such as the Rhône and Inn valleys, which lie between mountain ranges and support major settlements.