In this paper a complete strategy for scene modelling from sensory data acquired in a natural environment is defined. This strategy is applied to outdoor mobile robotics, from environment recognition to landmark extraction. In this work, an environment is understood as a specific kind of landscape, for instance prairie, forest, desert, etc. A landmark is defined as a conspicuous object in the environment. In the context of outdoor mobile robotics a landmark has to be useful to perform localization and navigation tasks.