Transfer of Development Rights and Cultural Heritage Preservation: A Case Study at Athens Historic Triangle, Greece

History and the modern world co-exist in Greece's landscape. The urban spaces of Greek cities contain structures from ancient history alongside contemporary constructions, but intense urban development from the 1960s onwards, as in the historic center of Athens, has led to imbalances with respect to cultural heritage protection. The 1975 Greek Constitution defined the preservation and protection of the cultural environment as a constitutional mandate, and severe restrictions on the exploitation of private properties deemed to be of historical or architectural importance were imposed. Property owners were deprived of their property development rights (DRs), whereas the preservation and conservation of protected constructions became costly, resulting in abandoned buildings and a downgraded urban environment. As the debate over cultural heritage protection and urban regeneration is more topical than ever, the recent legal reintroduction of the transfer of development rights (TDRs) provides new opportunities for property exploitation with respect to cultural heritage protection legislation. Herein is presented a methodological framework on the classification and 3D visualization and representation of DRs and TDRs in relation to the cultural heritage protective framework and its implementation in a selected area of Athens' historic center. Legal and technical aspects that affect 3D DRs and TDRs are emphasized as key elements in the successful implementation of the TDR process.