During the intensive observational periods of the BERLIOZ campaign (20 and 21 July 1998 and 3 August 1998), vertical profiles from 0 to 800 m above ground of O3, NO2, NOx, selected VOC, and meteorological parameters were measured by means of a comprehensive tethered balloon system at Papstthum, a rural site 50 north west of the city of Berlin. Every 2 hours a complete profile was obtained. The VOC were collected on charcoal tubes simultaneously at four different heights over time intervals of 3 hours. The measurement systems participated at the quality assurance measures of the BERLIOZ campaign and fully complied with the data quality objectives. The balloon data provide important information on the vertical gradients of the trace gases at Pabstthum and clearly identify the development of the boundary layer in the course of the day. This information is important for the interpretation of the radical measurements discussed in the accompanying publications. They also give insight in the vertical extent of air masses of different chemical regimes and their temporal evolution. During the morning hours of 20 July the evolution of the city plume passing the measurement site with a vertical extension of 800 m could be documented. Owing to degradation by the reaction with NO a reduced O3 concentration level was observed within the plume in the morning hours of 20 July. The highest peak concentrations of the campaign observed on ground level in the morning of 21 July could not be attributed to the Berlin city plume.