One of the most critical issues in large-scale software development and maintenance is the rapidly growing size and complexity of software systems. As a result of this rapid growth there is a need to better understand the relationships between the different parts of a large software system. In this paper we present a reverse engineering framework called Columbus that is able to analyze large C++ projects, and a schema for C++ that prescribes the form of the extracted data. The flexible architecture of the Columbus system with a powerful C++ analyzer and schema makes it a versatile and readily extendible toolset for reverse engineering. This tool is free for scientific and educational purposes and we fervently hope that it will assist academic persons in any research work related to C++ re- and reverse engineering. Keywords Tool interoperability, standard exchange format, C++ schema, front end, ASG, Columbus/CAN, GXL