This paper is concerned about the production of open source tools for development of training simulators in particular and any kind of applications in general that need real-time visualization of large geographical environments. The purpose is to use these tools in projects of the Ministry of Defense at first, to finally open them to the rest of the Government and the community. The proposed solution is based on OpenSceneGraph (OSG), which is an open source visualization engine, and Common Database (CDB), which is an open standard for systems oriented geographic databases with visualization of large geographic environments. CDB is a synthetic environment database specification and OSG is an open source high performance 3D graphic toolkit widely used by the simulation, spatial, scientific visualization, games and virtual reality industries and it supports many of the same formats used by CDB. This paper presents the design and implementation of a CDB visualization technique that uses OSG. The solution composes OSG compatible SG’s from CDB nodal data so that datasets can be shared, reused and made extensible. The elevation imagery example described in this paper includes an evaluation of loading times and frame rates. The results indicate this is a real-time solution that can be applied across large synthetic environments to visualize data stored in CDB databases using OSG as the image generator.Sociedad Argentina de Informática e Investigación Operativa