The archaeological site of Palaiokastro (Old Navarino castle), is located in Messenia on the Coryphasium peninsula, at the southern end of the beach of Voidokoilia in the Navarino Bay, SW Peloponnese. Palaiokastro was built during Frankish rule of the Peloponnese, in the 13th century, over the classical Acropolis of Pylos.The aim of this study is the initial documentation of the current situation of the medieval castle of Palaiokastro applying innovative technology including terrestrial laser scanner (TLS) and unmanned aerial vehicles (UAVs). TLS and UAV photogrammetry have been used in an integrated design to rapidly facilitate the acquisition of the whole gate, eliminating all possible occlusions. TLS was exploited for the acquisition of the facades while the UAV was used to capture the top view of castle gate. The recent improvement of the post-processing algorithms provides us with the ability to implement fusion methods of TLS and UAV models and also deliver an accurate 3D model of the whole gate.The combination of photogrammetry from the UAV with the data of the terrestrial laser scanner was used in order to give us a multitude of products such as textured 3D model, orthophotos, 2D floor plans, elevations and sections which are necessary for the complete and accurate geometric documentation of the current situation of the Southwest gate of Palaiokastro Castle. The various products mentioned assist in the better management of the study data and identification of the different construction phases of the South Gate.