Uploaded on 2014-10-24 by alidalaf

[1]: https://edxuploads.s3.amazonaws.com/14141711899478068.jpg I took this photo in august 2013 in Istanbul . **The visible:** There are many visible data like the way & materials of construct the building (the towers), traffic & street guidelines. But there arr more **invisible** data like the growth of Turkey economy, the increasing of tourists that comes to Istanbul , the nice weather in Istanbul, the underground electricity network.