Liquid flow experiments, in which a tracer was introduced as a point source, were performed in a thin two-dimensional packed bed. These simple experiments demonstrated the essential features of hydrodynamic dispersion in packed beds, The standard Fickian-type model and the wave model were compared with respect to their ability to describe the tracer propagation. The wave model does so adequately, in contrast to the erroneous predictions by the Fickian-type model. Arguments are provided to show that the application of hyperbolic-type equations improves the description of dispersion in packed-bed reactors.