A one‐dimensional deterministic slope stability model (infinite slope model) was used to calculate average safety factors and failure probabilities for the city of Manizales, in central Colombia. An engineering geological data base has been created on the basis of a series of parameter maps (geology, geomorphology, Digital terrain models and slope classes), using logic reasoning in Geographic Information Systems (GIS). A two‐dimensional hydrological model was applied to estimate groundwater levels in relation to rainfall events. A simple method for the calculation of horizontal seismic acceleration was used for different earthquake events. To calculate average safety factors a number of scenarios were developed, by combining the effects of groundwater and seismic acceleration with different return periods. A simple method for error propagation was used to calculate the variance of the safety factor, and the probability that it will be less than 1, for each pixel, within a time period of 20 years. The highest probability value of the various scenarios was selected for each pixel, and a final hazard map for translational landslides was constructed. The results presented here are a first approach towards a deterministic landslide hazard analysis using GIS. It has a number of drawbacks, which should be solved in future work.