The network described in this paper has been set up to provide detailed time-series data on concentrations of 222Rn in air at various locations within the Alligator Rivers Region, over a time frame of several years. These data will be important in assessing the effects of uranium mining operations on radon levels in the region, both in providing baseline and monitoring data and in calibrating and verifying predictive models. At present, three stations are operating in the region with a fourth being commissioned. Each station logs half hourly average radon concentrations and relevant meteorological data (wind speed, direction and variability, air pressure and temperature, relative humidity, soil temperature, rain and sunshine rates). It is intended to operate the four stations at selected locations for one- or two-year intervals, at the end of which three will be moved to new locations (one station at Mudginberri will be kept as a constant control station). Sites for which extensive datasets are currently available include: Jabiru Town, Jabiru East, Djarr Djarr, East Alligator Ranger Station and Nabarlek minesite. Illustrative data from these sites are presented.