Using Remote Sensing, Laser Scanning and GPS for Documentation of the Historical Byzantine Aydos Castle

摘要

Sultanbeyli district, one of the 40 districts in Istanbul in Turkey, is located in the Asian side of the Istanbul Metropolitan area. Aydos Castle in the Sultanbeyli district covers an area of 25,000 m2 on a high hill. It is known from different documents that this castle used to be an important center in the east border of the late Byzantine Empire. During 1326-1328 Ottomans invaded a large part of the Kocaeli Peninsula and parts of the settlements in the Asian side of Istanbul. During this period, the line between Aydos and Pendik defined the border between Ottoman and Byzantine Empires. In 2009, a restoration project of the castle was started. Firstly, there was a need to determine the current situation of the castle and its surroundings and to design a documentation project to be used as a technical basis for restoration studies. For its documentation, advanced techniques, such as remote sensing, digital photogrammetry, terrestrial laser scanning, GPS and different surveying methods were used. To determine the current situation, images were taken from different platforms, such as crane, helicopter and model plane. The 3D model of the castle was obtained from terrestrial laser scanning. The site plan of the castle surroundings was produced by differential GPS system. Weeds and some of the obstructing trees on the hill, based on an agreement with the forest authorities in Istanbul, were cut down; stones inside the castle were removed and the castle became ready for a detailed archaeological excavation. The excavation was undertaken by a team of sixty people under the supervision of the Istanbul Archaeology Museum and two large bastions and walls were revealed. As a result of all these studies, a documentation project was prepared, historical sources were analysed and a comparative restoration report was completed by examining similar castles. This paper gives general information about different documentation methods used during the project.