A cirque is an amphitheatre-like valley of glacial origin, formed by glacial erosion at the head of the glacier. They are typically partially surrounded by steep cliffs The highest cliff is often called a headwall. They are also known as a cwm in Wales, a coomb in England and a corrie in Scotland and Ireland. Download high resolution version (1024x768, 137 KB)Photo of Iceberg Cirque, courtesy Glacier National Park, US National Park Service. ... The name amphitheatre (alternatively amphitheater) is given to a public building of the Classical period (being particularly associated with ancient Rome) which was used for spectator sports, games and displays. ... Fljótsdalur in East-Iceland A valley is a landform, which can range from a few square miles (square kilometers) to hundreds or even thousands of square miles (square kilometers) in area. ... Mouth of the glacier Schlatenkees near Innergschlöß, Austria. ... Look up Erosion in Wiktionary, the free dictionary Severe soil erosion in a wheat field near Washington State University, USA. Erosion is the displacement of solids (soil, mud, rock, and so forth) by the agents of wind, water, ice, movement in response to gravity, or living organisms (in the case... National motto: Cymru am byth (Welsh: Wales for ever) Waless location within the UK Official languages English(100%), Welsh(20. ... Royal motto: Dieu et mon droit (French: God and my right) Englands location within the UK Official language English de facto Capital London de facto Largest city London Area - Total Ranked 1st UK 130,395 km² Population - Total (mid-2004) - Density Ranked 1st UK 50. ... A corrie on Ben Lui in Scotland In geography, a corrie, is a terrain feature created by glaciation in high mountains. ... Royal motto: Nemo me impune lacessit (Latin: No one provokes me with impunity) Scotlands location within the UK Languages with Official Status1 English Scottish Gaelic Capital Edinburgh Largest city Glasgow First Minister Jack McConnell Area - Total - % water Ranked 2nd UK 78,782 km² 1. ...

Many glacial cirques contain tarns dammed by glacial till. Cirques form in conditions which are favorable, which in the northern hemisphere includes the north-east slope being in shade and away from prevailing winds. These conditions are sheltered from heat, and so encourage accumulation. A tarn is a mountain lake or pool, formed in a valley excavated by a glacier. ... Categories: Geology stubs | Glaciology | Sedimentary rocks ...

Once accumulation has begun to occur, and snow is forming, a process of nivation occurs. This is where a hollow in a slope is enlarged by freeze-thaw weathering, and meltwater (from melted snow) transporting the broken debris away. Eventually this hollow will become big enough to let glacier ice begin to form (where glacier ice is compacted snow). Debris in the ice begins to abrade (glacial abrasion) on the bed surface which further enlarges the hollow into a small basin.

Eventually the hollow is a large bowl shape in the side of the mountain, with the headwall being weathered by freeze-thaw and eroded by plucking, and the basin becoming deeper as it is eroded by abrasion.

Notable cirques include:

• The Cirque de navacelles, France
• The cirque de Cilaos, Réunion