This Diploma Thesis deals with the design of a Cultural, Educational and Leisure Complex in the area of Ai - Yiannis Detis on the island of Paros, which is the favorite place of the student. The lack of a hyperlocal Cultural Center on the island and the need to highlight the important cultural activity of the Parians, led to the idea of redesigning the "core" of the infrastructures of Paros Environmental and Cultural Park in the peculiar natural beauty and history peninsula of Ai - Yiannis Detis. The intention is to create there a modern complex, which will attempt to "reinforce" the use and "interact" with the dominant existing outdoor infrastructure of the Theater, which is "embedded" in the unique geological landscape - rocks of Ai - Yiannis. Through cultural events, educational activities and recreational uses, such as exhibition space, small Geological Museum, multipurpose hall, educational workshops, refreshment, restaurant etc., it aspires to be a landmark for Paros and a public cultural attraction. A "crowd capacitor" active all year round and for all ages, both for locals and for domestic and foreign visitors. The aim is to promote alternative forms of tourism, such as the modern quality cultural tourism and others. It is a gentle intervention with an attentive scale that respects the environment and is fully integrated into the natural landscape and terrain. The entire Composition is a semi-underground platform that could be considered as a miniature of a Cycladic settlement core, because independent linear building structures are joined under a single fordable and planted slab which has holes and creates passages, open-air, semi-outdoor and closed spaces. It follows the basic synthetic principles of Cycladic architecture with a modern perspective and consists of the rocks of the region that make up the stone-bearing walls, the masonry, the columns and the benches, of reinforced concrete that constitutes the single slab, the beams and the floors, as well as of the excavation products.