Abstract. The presence or absence of preferential flow strongly controls water flow and transport in soils. It is ubiquitous, but difficult to characterize and predict. This study addresses the occurrence and the evolution of preferential flow during the evolution of landscapes, and here specifically during the evolution of hillslopes. We targeted a chronosequence of glacial moraines in the Swiss Alps to investigate how water flow paths evolve along with the soil forming processes. Dye tracer irrigation experiments with Brilliant Blue solution (4 g/l) were conducted on four moraines of different ages (30, 160, 3000, and 10 000 yrs). At each moraine, three dye tracer experiments were conducted on plots of 1.5 × 1.0 m. The three plots at each moraine were characterized by different vegetation complexities (low, medium, high). Each plot was further divided into three equal subplots for the application of three different irrigation amounts (20, 40, 60 mm) with an average irrigation intensity of 20 mm/h. The day after the experiment five vertical soil sections were excavated and the stained flow paths were photographed. Digital image analysis was used to derive average infiltration depths and flow path characteristics such as the volume and surface density of the dye patterns. Based on the volume density, the observed dye patterns were assigned to specific flow type categories. The results show a significant change in type of preferential flow paths along the chronosequence. The flow types change from a rather homogeneous gravity driven matrix flow in coarse material with high conductivities and a sparse vegetation cover at the youngest moraine to a heterogeneous infiltration pattern at the medium-age moraines. Heterogeneous matrix and finger flow are dominant at these intermediate age classes. At the oldest moraine only macro pore flow via root channels was observed in deeper parts of the soil, in combination with a very high water storage capacity of the organic top layer and low hydraulic conductivity of the deeper soil. In general, we found an increase in water storage with increasing age of the moraines, based on our observations of the reduction in infiltration depth as well as laboratory measurements of porosity. Preferential flow is, however, not only caused by macropores, but especially for the medium age moraine seems to be initiated mainly by soil surface characteristics (vegetation patches and micro-topography).