The first continuous measurements of the hourly surface ozone (O-3), nitric oxide (NO) and nitrogen dioxide (NO2) concentrations at 7 rural and 15 urban sites in Marmara Region of Turkey during the period from March 2013 to April 2016. The results indicate that surface O-3 is an extensive problem throughout the Marmara Region. O-3 levels have similar seasonal pattern in rural and urban sites by following the order of summer, spring, fall, and winter. The seasonal results showed an opposite behaviour among O-3 and NOx (NO + NO2) in both rural and urban sites, marked by maximums (minimum NOx) of O-3 in summer and minimums (maximum NOx) in fall and winter. The summer concentrations vary between 91.5 and 123.6 mu g/m(3) and 74.6-112.4 mu g/m(3) at rural and urban sites respectively. Furthermore, O-3 peak concentration time in rural areas in O-3 seasons (April-September) occurred at around 17:00-18:00 LST while in urban areas at around 15:00-16:00 LST, respectively. Air quality standards for O-3 concentrations in Sile and Yalova rural sites were significantly exceeded during O-3 season. This exceedance made a linkage between back trajectories and air masses with respect to the O-3 levels. 72-hr back trajectories at an altitude of 500 m agl were computed by HYSPLIT model to assess the type of air masses which reach the area. AOT40 (accumulated exposure over a threshold of 40 ppb) index was performed for both vegetation and forestry standards and EU Directive were significantly exceeded at all rural stations.