Computerized 3D modelled spaces are thought to be reliable imitations of Real Environments (REs). Depth perception in displayed Virtual 3D Environments (VEs) is a controversial issue. The present work compared both egocentric and allocentric distances in a RE and a VE. Results showed more errors in the VE (underestimations) than in the RE (overestimations), and a gender effect in the different environments mediated by Mental Rotation ability. Findings suggested that spatial and perceptual processing underlying artificial 3D modelled space may not be similar to cognitive spatial processes in REs.