TETRAGONO is a bus station and a shoreline project which creates a link between two historical points of Egirdir, Isparta: the castle and the Hizir Bey Mosque. The main aim is to connect the lake and the mosque square by recreating a bus station as a transportation hub without changing its location. Shore treatment is made by using green parks consisting of bioswale systems in order to harvest the rainwater and create a cycle cleaning the lake water. Beside the parks, the shore treatments also have various pavement styles creating playgrounds and some building programs like auditorium, restaurants, and a bus station are introduced. The focused point is the bus station which is design using local materials.