Documentation and measurements on historical buildings are mostly connected with close-range photogrammetry for high resolution in order to analyse the detailed structure of the objects. Classical flight campaigns are expensive, limited by the resolution or restricted. An alternative with immediate access to the data is the use of a helium-balloon based platform with digital camera. For a project in the southern part of Turkey has been developed a system with a He-Balloon, a digital camera, a control-monitor and a mechanic stabilization. As digital camera was chosen an Olympus Camedia 4040 with 4 Mega-Pixels, which has been calibrated. The Camera was fixed in a triangle frame on 2 axes, so that it had always nadir view. The triangle frame was fixed with 6 ropes below the balloon, and to the ground with 3 ropes, one carried a video and control wire. The video signal of the cameras view was sent to a monitor and the remote control of the camera was also solved by wires. Then a flight-campaign in August 2002 was made over an excavated historical theatre in the former city of Patara, the former major port of Lycia, located at the mouth of the Xanthos River. In the presentation we want to show you the technical solution and the results of this campaign. The accuracy of the aerial images was better than 4 cm in position and height, the digitising however complex, related to the objects structure. The 3D-Vector data built the base of a fine DTM. Orthophotos have been created in order to add information the digitised results.