Slope angles

Slope angles play a key role when planning your alpine or winter activities. The steeper the terrain, the greater the risk of an accident or an avalanche.  We aim to help you assess the risk by providing colour coded slope angles on some of our maps for Western Europe.



Where does the data come from?

We use digital terrain models to generate shading and contour lines. We try to research the most suitable data for each country and integrate this into the map.


Availability of slope angles

The slope angle layer covers the bulk of Europe and is available in the following countries and areas as part of these maps:


OpenStreetMap map:

20–90m of resolved data in the following countries:

Portugal, Spain, Andorra, France, Switzerland, Liechtenstein, Luxembourg, Belgium, Netherlands, Germany, Austria, Italy, Slovenia, Great Britain, Denmark, Norway, Sweden, Finland, Latvia, Estonia- as well as for the Rocky Mountains.


The Outdooractive map:

10m resolved data in Germany, Austria and parts of Northern Italy.  Within selected products, a slope with 2m data in Switzerland or 5m data in France is available.

The intended use of the slope angle layer

Slope angles in the Alps provide critical information to ski tourers, freeriders or alpinists who are away from marked areas or designated trails and therefore have to assess the risk of avalanches.

They play a key role in the decision-making instruments that are common in Europe (e.g. 3x3, graphical reduction method). These methods take several factors into account when assessing avalanche danger:

  • Avalanche Conditions (the level of danger according to avalanche warning services, weather, frequency of avalanches)
  • Terrain (slope, exposure, danger spots)
  • Human factors (group size, safety precautions) 

These parameters should be used both in the initial planning phase and in a further assessment at the concerned area itself,  to determine whether the level of risk posed for skiing and climbing in that area is acceptable.

The aim of our slope angle layer, which is divided into multiples of 5°, is to provide a more accurate picture of the terrain, this should be factored into your planning and risk assessments.

Slope angles on the map and in the Route Planner

The slope angles on our map are displayed from a zoom level of 500m on our summer, winter, and satellite styles. The darker the color, the steeper the slope.

When planning any trips that involve ski touring, snowshoe walking, backcountry skiing, ice climbing or glacier hiking using the Route Planner, the slope angles for that area will be automatically displayed on the map. This feature can be switched on and off manually for all activities.

How do I manually activate the layer?

The layer is activated via the ''maps and trails'' layers section at the bottom right of the map screen both in the app and on the website. Select from OSM, Outdooractive or topo maps → scroll down and activate the "Slope Angle" under "Additional layers".

Safety advice

As already mentioned, the slope angle is an extremely important factor in avalanche risk management. However, it should be noted that even the best terrain maps- can only ever provide a limited view of actual conditions.

The representation of an average incline over a range of several meters can mean that short but extremely steep slopes or breaks are not depicted on the map, even though they exist in reality.

For this reason, slope angles should never be the only factor you use when planning your trip. We would highly recommend that you attend courses on avalanche risk assessment and consult further literature on the subject. 

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