Yarımburgaz Mağarası

Yarımburgaz Cave opens onto the slope of a rocky hill in the Altınşehir quarter of Başakşehir, roughly 1.5 kilometres north of Lake Küçükçekmece. According to Başakşehir Municipality, it lies about 22 kilometres northwest of central Istanbul and just north of Altınşehir. The cave formed when groundwater dissolved Eocene limestone, and its mouths face the Sazlıdere valley. It has two connected sections, which open to the outside through separate entrances at different heights. The Upper Cave is a broad hall measuring about 15 by 52 metres, reaching some 10 metres in height near the entrance. The Lower Cave begins as a gallery and then winds like a tunnel deep into the hill. According to the TAY Project records, this lower branch runs for about 600 metres and forks roughly 240 metres from the mouth. The two sections are linked by a short, sloping passage near the entrance. The mouths lie roughly 11 to 18 metres above the level of the Sea of Marmara. A dry valley running at right angles to the Sazlıdere on the east side of the rock is interpreted as a trace of the old watercourse that formed the cave. Because bedrock was reached only near the mouth of the Lower Cave, the cave's true height has not been determined. The cave entered the scientific record in the mid 19th century, and sources name Abdullah Bey as the first to describe it. The first excavations took place in 1963 at the entrance of the Lower Cave, led by Şevket Aziz Kansu and directed by Kılıç Kökten. In 1964 and 1965 the cave was divided into grid squares and excavated more systematically. In 1986 a rescue excavation was carried out under Mehmet Özdoğan of Istanbul University. Between 1988 and 1990 Istanbul University and the University of California at Berkeley ran a joint project; Güven Arsebük directed the excavations and the palaeoanthropologist F. Clark Howell was part of the team. The excavations showed that, taking both sections together, the deposits in the cave are more than 10 metres deep. In the Upper Cave, layers were identified from the Byzantine, Late Roman, Chalcolithic, Neolithic and earlier phases, from the most recent downwards. In the Lower Cave, Palaeolithic stone tools were found together with large numbers of cave bear bones. The tools include flint flakes as well as pieces made of quartzite and quartz. Most of the large mammal remains belong to bears, with more than 5,000 fossil bones and teeth recovered. Sources give different figures for the age of Yarımburgaz; Turkish sources speak of a past of more than 400,000 years, while the dating studies summarised in the English Wikipedia point to the later part of the Middle Pleistocene. What is certain is that the cave is one of the rare places in Thrace to yield stratified Palaeolithic finds. In the Byzantine period the walls of the Upper Cave were dressed and the space was used as a church, and a related monastery building is said to have stood outside the cave. Beam holes in the walls show that a tiled upper floor was built inside. Some finds from the cave are on display at the Istanbul Archaeology Museums. The cave was declared a first degree archaeological and natural protected site in 2001. During the 1988 excavation both mouths were closed with iron bars to keep out treasure hunters. Bars can still be seen at the entrances today and the cave cannot be entered; visits are made from outside, along the paths in front of the rock face. Within the protected area, do not touch the excavation traces, the rock or the bars, and do not move stones on the ground. The best view is from the foot of the slope, where the arched mouth of the Lower Cave and the Upper Cave opening above it can be seen together. The shapes of the limestone rock stand out in the side light of the afternoon. Paths on the slope can become slippery after rain, so wear shoes with good grip. The cave is reached via the road running from Halkalı to Altınşehir; check current bus routes with İETT. Nearby, the shore of Lake Küçükçekmece and the Sazlıdere valley are open spaces that can fill the second half of the same day.