The National Institute of Geographic and Forest Information (Institut National de l'Information Géographique et forestière) analyses, and provides cartographic representations of, French national territory, including its famous "IGN maps" and essential topographic hiking maps.
Cairn Pyramid of different sized rocks used to mark a trail and help hikers find their way.
This term refers to the difference in height between two points. The French term for "elevation" (dénivelé) is the subject of not inconsiderable controversy: although historically a feminine word, it has been used incorrectly as a masculine noun. Today in France, this non-conventional masculine use has now become the norm.
Not to be confused with elevation. A slope corresponds to the tilt angle of a vertical surface. We use the term slope when the angle between the ground and the wall is less than 90 degrees.
An adret slope is the land on the side of a valley that receives the most sunlight. Conversely, an Ubac slope refers to the opposite side.
The terms upstream and downstream are very useful for getting your bearings. On a path between a mountain pass and a valley, for example, UPstream indicates the side that goes UP to the mountain, while DOWNstream indicates the side that goes DOWN to the valley.
Firn is an isolated area of persistent snow (you can even encounter firn in summer). A firn layer usually forms in areas where there is little sun exposure. Not to be confused with permanent snow.
(Or "snow line"). Permanent snow is seen in mountainous areas where days of heavy snowfall outnumber snow-free days. A number of different factors (sunshine, atmospheric pressure etc.) means that precipitation in this area falls as snow, ensuring the peaks remain snow-capped. This snow is not "permanent" but rather constantly replaced!
A pile of ice formed by the accumulation of layers of snow. A glacier comprises several parts: bergschrund, moraine and serac.
A Bergschrund is a crevasse that forms at the edges of the glacier, separating it from the original landform. The area between the glacier and snow or ice slope is referred to as the bergschrund; the area between the glacier and rock wall is referred to as the roture. They are formed by the glacier's movements.
Moraine is an accumulation of rock debris transported by the moving glacier.
A large block of ice, partially detached from a glacier. Seracs are formed when glaciers fracture and crack.
A very narrow, enclosed corridor of snow or ice that often forms in dihedrals (a dihedral is the name given to the area where two planes of rock intersect to create an acute angle).
This is the name given to a circular or semi-circular (arena-like) shaped mountain. This shape may be the result of erosion or indicate the presence of an old glacier or volcano.
Accumulation of wind-blown snow on a ridge. This mass of self-supporting snow often forms an overhang, protruding beyond the ridge, posing a real hazard if it falls.
Climbing rock faces or rocky structures. Rock climbing, when hiking, involves using your hands to negotiate certain steep sections of the ascent.
Temporary outdoor camp. A bivouac camp is set up in the evening and then dismantled the next day (at sunrise). This prevents natural parks being turned into camp-sites, ensuring they remain tent-free during the day. Check out our advice on bivouacking.
To take full advantage of your mountain treks, we suggest some safety reminders specifically applying to hiking. Don't forget to tell a friend before you leave, prepare your first aid kit, keep your vaccinations up to date, and protect your skin from little creatures. Nothing will stop you from going on the adventure!