The large recreational park on the outskirts of Oberlaa contains more than a dozen sculptures by various authors, made during an international open-air workshop in 1974 when the parkten was founded. One of the most interesting was the work of Maciej Szankowski, but it has been collapsed and lying in pieces among the trees for many years now. It is not known when exactly the sculpture was damaged. Szańkowski participated in several sculpture plein-airs abroad, realising large abstract constructions in metal, stone or concrete. From the early 1970s, he experimented with various materials, creating subtle spatial constructions that seemed to defy the laws of gravity, operating with delicate tilts (e.g. the work at the Nuremberg symposium), a perverse play of verticals and levels, etc. The thin granite pillars, carved in granite during an international sculpture symposium in Vienna, originally stood on a high pedestal, one metre apart, forming a kind of gateway through which two broken, recumbent beams, with shapes and incisions analogous to the pillars and inspired by wooden construction, seemed to pass smoothly. These perhaps suggested the idea of a '(...)tori-Japanese gateway to heaven.' This latter hypothesis would be supported by the fact that tori were always made of wood, and in the Oberlaa sculpture, for the second and last time in his oeuvre - as in his 1964-65 Space Studies - Szańkowski does not respect the properties of the material, but imitates the shape of wooden beams in granite" (Bożena Kowalska). Two years later, a similar reflection on elementary architectural forms resulted in a much larger open-air realisation in Maribor. And in the same year, 1974, Szańkowski erected a monumental metal composition of spheres in Warsaw, on the Kopernika estate, in a completely different style to the Viennese work.