Along the south coast of Turkey in Mersin Province, several massive megalithic sites with polygonal and cyclopean walls exist, hidden in the hills and mountains. Remarkably similar to sites in Italy, Greece and even Peru, these structures are thought to be Hellenistic (Seleucid Empire) built around 2300 years ago. The site of Meydan Kalesi (Square Castle) has rock-cut hypogeum features, 3D relief carvings and Tiwanaku-like monolithic doorways, yet it is unclear who may have built the first phase of megalithic construction. Includes exclusive aerial footage.