He devoted most of his energies to the development of MUSABA: a project of meetings, internship, projects and environmental, architectonic and artistic works. In 1973, Nik and Hiske inaugurated the event “Struttura Ambiente”, which was to become one of the main features of the history of MuSaBa. Their aim was to enhance land and environment through sculpture-structure. Spatari was the main producer of the monuments designed by artists throughout the world for the new Artistic Park. His artistic-architectonic skills and technique allowed him to transform drawings and models into structural monumental works (made with “poor” materials”) of unusual beauty and which were in perfect harmony with the surrounding environment.
At MuSaBa, they organized, with Pierre Restany, an international meeting on the relationship between art, architecture and environment, where some of the main contemporary artists took part. He involved Zevi, Bonito Oliva, Gallo, Portoghesi, Burri, Schifano and Rotella.
He took part in the 10th Quadrennial in Rome and had solo shows in Toronto, Montreal, Amsterdam, London, Brussels, Kopenhagen, Zurich, Geneva, Venice, Milan, Turin, Bologna, Florence, and Palermo. From varnish and enamel, he moved to nitre, which was more suitable for the frottage technique and for his new subjects. In this period he worked on big canvases, i.e. “Cavalieri extraterrestri” (Extraterrestrial Knights) and “donne-idolo” (Idol-women) from the Sumerian mythology.