Main goal of this bachelor work was research of the subsurface at Václavské náměstí square in Olomouc and detection of noted features of the underground. Ground Penetrating Radar (GPR) machine developed by Geophysical Survey System Inc. (GSSI) was used during this research.

         Underground of the square was detected by GPR and collected data were processed at RADAN 6.6 software by GSSI. Results were displayed in form of maps, 3D data’s pictures and all detected profiles were put into CD with free RADVIEW software which is used to display this data.

         Full process of collecting data by GPR was described in detail to help other users collecting analogical data in future. Basic postprocessing of data in RADAN software is described, especially creating and control of 3D project and Super 3D project.

        Export of results from software RADAN to other GIS apllications especially ArcMap 9.2 by ESRI is also described, as well as process of interpretation data, which is the most important and difficult part of every work with GPR.