A macroradiographic technique for measuring radon exhalation of various soils in Hungary has been developed. The method is based on long-term simultaneous measurement of the alpha-activity of soil gas at numerous points of a given area with plastic nuclear track detectors. In the present work a two-year experience related to calibration measurements in laboratory, methodical studies on stationary points of field basic stations and mapping of radon anomalies over different geological profiles is surveyed. Several casestudies are presented, to show the effectiveness of radon macroradiography in revealing geological structures below the area to be explored.