Debris flows and debris avalanches represent a large threat to society in Norway. The intensity and frequency of these events is expected to increase over the course of the next 50 years due to changing precipitation patterns related to global climate change. Models are continually being developed and tested to better understand and characterise these events. An important part of creating regional and local-scale hazard maps is understanding the potential runout distance and velocity that can be achieved by these events. This thesis provides a detailed study of four landslide events in western Norway (two debris flows and two debris avalanches) additionally, it compares two software packages used for landslide back-analysis. The work presented is part of the Klima2050 research initiative. Field visits were conducted at each site in order to develop a better understanding of the event geometry and take soil samples to construct grain size distribution curves for each event. These grain size distributions were used to estimate the static friction of each soil sample. Landslide back-analysis was conducted using DAN3D to determine rheological parameters for each event. Simulations were also conducted in GeoClaw, to compare it with DAN3D and determine its suitability for the runout modelling of debris flow events. Dynamic friction angles calibrated in the models were compared to the static friction angles obtained from the grain size distributions. Simulation results agree with field observations of the debris flow and debris avalanche events. DAN3D was found to underestimate the runout of the landslide events, but simulations were a good fit with the path geometries. GeoClaw overestimated the material mobility and did not include material entrainment. Therefore, DAN3D is currently the more viable of the two programs for accurately modelling and characterising debris flow and debris avalanche events.