Abstract. We report measurements of the surface topography of a 70 nm gold film deposited on mica preheated to 300 oC in UHV performed with a Scanning Tunneling Microscope (STM). From these measurements we determine the rms roughness amplitude and the lateral correlation length characterizing the average height-height autocorrelation function on a nanometric scale.We also report a method of analyzing thin film resistivity data that departs sharply from the traditional method of parameter fitting. This method allows the determination of the resistivity and mean free path characterizing the bulk from the measured thin film resistivity by means of a new iteration procedure, that uses as input data the roughness parameters experimentally determined with the STM and any of the available quantum transport theories, without adjustable parameters. We examine the resistivity data reported by Sambles et al. [Philos. Trans. R. Soc. London, Ser. A304, 365 (1982)] for gold films deposited on mica under similar substrate temperature and similar speed of evaporation. The remarkable outcome is that any of the quantum transport theories available, describe approximately both the temperature as well as the thickness dependence of the resistivity data without any adjustable parameter. Another surprise is that the parameters characterizing the bulk—assumed to be independent of thickness for many years—turn out to be thickness dependent.