The initial stages of the anodic oxidation of Au(111) were investigated by means of cyclic voltammetry as well as in situ scanning tunneling microscopy (STM). The results suggest that the place exchange process, which initiates the oxide formation, starts at step edges. The oxide phase was imaged in situ by scanning tunneling and atomic force microscopy (AFM). The topographic information acquired by the two techniques is compared. Keywords: gold, gold oxide, corrosion, scanning tunneling microscopy (STM), atomic force microscopy (AFM).