A comprehensive radiological survey using multivariate statistical analysis was carried out to evaluate the distribution of 40 K, 232 Th, 226 Ra, 235 U, and 137 Cs, and associated radiation indices in beach sand samples of the coastal area of the Aegean Sea. The activity concentration of selected radionuclides was measured and no clue of recent migration of radiocaesium by not only precipitation but also through an indirect way, such as ocean runoff, was found. As part of radiological risk assessment, external radiation hazard index, radium equivalent activity, effective dose, and absorbed dose rate were estimated. Pearson correlation, cluster, and PCA analysis were used by processing observed radiological parameters to determine the correlation between the radiological parameters and locations. Pearson correlation shows a strong association between all parameters and activity of 226 Ra and 232 Th. A spatial distribution map was provided to a distinct visual representation of the distribution of radionuclide contents in the study area. • A comprehensive radiological survey in northern Aegean Sea coastline • Covering 300 km and 11 coastal zones • Measuring activities of natural and artificial radionuclides in sand samples • Spatial distribution maps of radionuclides in Chalkidiki region