Large landslides affect many mountain valleys in Europe. They are characterised by a low probability of evolution into a catastrophic event but can have very large impacts on population, infrastructures and the environment. This impact is becoming more and more pronounced due to increasing tourism and the construction of new roads and railways in mountainous areas. Methodologies for the assessment and mitigation of risks are therefore a major issue. Since very large slope movements are quite often directly or indirectly implicated in disasters, like landslides, secondary slides or debris...