The increasing interest about the environment and the conditions for a safe and healthy life require continuous monitoring of physical and chemical parameters in the urban areas as well as in specifically dangerous surroundings (proximity of plants and hazard sites). Aside from the important consideration about risk and protection of the monitoring crew, the costs of extensive, specialist operators have also to be taken into account. In such a frame, autonomous vehicles could conveniently carry on the repetitive measurements with a significant reduction in risk and costs. Looking specifically at the quality of the air, both terrestrial and aerial platforms could be used; yet the best solution would be their combined use. This research proposes indeed a monitoring system composed by wheeled rover, obviously extendable to more vehicles. These platforms map the state and the evolution of the pollution by means of a set of sensors (measuring LPE, CO, CO2, CH4, H2, NH4) purposely developed. A special focus is devoted to the autonomous guidance and navigation system, including inertial measurement unit, GPS and stereo vision that enables the operations.