Characteristics of radon transport in porous media were studied through both in situ and lab-scale measurements. In situ measurements of radon activity concentration, together with soil thoron and carbon dioxide efflux, were carried out on Mt. Etna volcano. More detailed information on radon transport mechanisms has been obtained from laboratory measurements. In particular, we report the first results of a systematic study carried out at the University of Catania (Italy) by means of a facility consisting of a large cylindrical stainless steel vessel, homogeneously filled with different materials. Radon concentration vertical profiles were extracted in low-moisture samples for different advective fluxes, temperatures and porosities.