As early as in the 8th century, Franks in the west and Avars in the east began building two opposite defense constructions, spreading from the outskirts of the Alps to the Drava River in the south. The area was long considered a bridge between middle and southeastern Europe and saw great battles of the Holy Roman Empire, Mongols, Osmans and other peoples for the dominance over the territory unfold in a period of over 1000 years. This border area is a notable remnant of the time, prominent for having one of the highest numbers of such defence constructions in the whole of Europe. Thirty years ago, the castles and mansions southeastern Austria were thus joined into a Castle Road (Schlösserstraße). Without the inclusion of castles and mansions from both countries, a comprehensive presentation of the border area’s most remarkable turning points and diverse history cannot be fully represented. Within the framework of previous meetings, 32 forts, mansions and castles that once formed the historic castle ring confirmed their participation in the project: Aichberg, Deutschlandsberg, Feldbach, Fürstenfeld, Gleichenberg  Gornja Radgona,  Grad,  Güssing, Hartberg, Herberstein, Kapfenstein, Kornberg, Lendava, Lockenhaus, Negova, Neuhaus, Obermayerhofen, Ormož, Ottersbach, Piber, Pöllau, Ptuj, Rače, Radkersburg, Rakičan, Riegersburg, Schielleiten, Schlaining, Seggau, Slovenska Bistrica, Tabor and Welsdorf. As the project unfolds, other castles and mansions will be invited to join. The project will research the historic and cultural background of the castles and mansions from the scientific and tourist standpoint, seeking to actively connect participants.  Special cross-border toursim products aiming at castles vacationers, families with children and cultural tourists will be developed and jountly promoted. The project result thus represents a cross-border union that connects castles and mansions of both countries and facilitates  joint marketing.