Mid-September - amidst the local harvest season with very agreeable climate and with the surrounding nature in one of its most beautiful states of the year - is a near-ideal time to visit Graz. Graz is the capital of the Austrian Province of Styria and with about 250,000 citizens Austria's second largest city. The unique Old Town of Graz was awarded World Cultural Heritage by UNESCO in 1999. A few years ago Graz was the European Cultural Capital 2003.

OPAC-3 will be held at Wegener Center of Climate and Global Change, located only a 10-min walk from the city center. Wegner Center for Climate and Global Change is located near by the University of Graz which hosts around 22,000 students of all disciplines and is, together with the Technical University of Graz (~10,000 students), the Medical University of Graz (~5,000 students) and the University of Music and Dramatic Arts Graz (~2,000 students), a main contributor to the appealing "Graz way of life" atmosphere so hard to miss for those who got to breathe it.