Pilot cross-sectional investigations of ambient submicrometer particles were conducted in five locations in the region of Salzburg, Austria. In conclusion, particle size distributions in the urban roadside environment of Salzburg are characterised by three peaks at approximately 0.04, 0.07 and 0.16 mm, the relative height of which varying for different days. Particle concentrations at the sampling sites located in the vicinity of traffic routes are up to 39104 particles cm3 and are on average an order of magnitude higher than at the suburban location isolated from an immediate impact of traffic. The mountainous non-roadside sites’ particle size distributions are different to those in the urban environment and are characterised by broader peaks shifted towards larger diameters. These sites have particle concentrations lower than Salzburg background. Traffic emissions did not affect airborne concentrations of other monitored pollutants to the same effect as particle number concentrations.