The first Forma Viva open-air sculpture workshops, initiated by Karl Prantl in 1959 at the St Margarethen quarry in Austria, inspired the Slovenian sculptor Janez Lenassi. Together with Jakob Savinšek, also a Slovenian, they organised two open-air workshops in Portorož in 1961, actually in Seča near Portorož and in Kostanjevica on Krka, in the first location the artists worked in stone, in the second in oak wood. Later, open-air workshops were held in two more locations: in Ravne na Koroška, where sculptures were created in metal, and in Maribor, where realisations in concrete appeared. At the end of the 1980s, Forma Viva ceased to operate everywhere except Portorož. In 1998, its activities were also re-established in Kostanjevica on Krka.

Symposia in Portorož were held every two years and attracted artists from all over the world, including Poland. A small group of artists was invited each year - the plein-air events ranged from three participants in 1965 and 1999, for example, to ten in 1963, among others. In general, a decline in the number of participants can be seen since the 1990s. The peculiarities of the political situation in Yugoslavia during the communist period allowed the organisers to be quite open to artists from outside the Eastern Bloc. Those outside Yugoslav artists are in the minority. Apart from Poles, 1971 saw the appearance of Czechs Jozef Jankivić (1973), Jaroslav Kubićka (1981) Miroslav Chlupać (1981), Peter Roller (1987) from Romania, Leonard Rachita (1981) and Marianov Bata (1987), both from Czechoslovakia, Janis Karlous representing the USSR (1983), Pavel Zoltan (1987) and Pavlov Dimco from Bulgaria (1989). After 1999, artists from Central and Eastern Europe, mainly from Slovenia and Croatia, were also shown. The last plein-air workshop was held in 2001.

Thanks to the wealth of local Istrian limestone resources, especially in places such as Marušići, Valtura and Kanfanar, and the region's strong stonemasonry traditions, Portorož and its surroundings were the ideal location for this project. Originally, the works were presented at the tip of the peninsula, but over time the collection grew and began to occupy more and more space in the park. In 1983, based on a presentation plan drawn up by art historian Stan Bernik, architect Vojteh Ravnikar designed the layout of the collection in the Portorož Sculpture Park. It assumed the preparation of an exposition written into the natural landscape and vegetation. Although Bernikar's original plan assumed spatial continuity of the original installations, subsequent realisations often deviated from these assumptions, which contributed to a more dynamic layout of the collection. Over time, the assumptions of the park's expansion also began to be realised, with some of the sculptures being located in Istria. However, most of the more than 130 works are located on the Seča peninsula within the park itself.

Polish artists who participated in the symposia and created their works in the park:
. Olgierd Truszyński, 1961
Ewelina Michalska, 1962
Alina Szapocznikow, "Biological Sculpture", 1963 (archival photos of rzêxba - https://artmuseum.pl/pl/archiwum/archiwum-aliny-szapocznikow/575/1084 )
Kazimierz Żywuszko, 1975
Adolf Ryszka, 1985