One of the Istanbul's most famous archaeological monuments, a historic tower located in Fatih area, suddenly collapsed a few days ago, and the old walls are in danger of falling as well.

A series of images shows deep cracks in the ancient historic walls of the city, that threaten of collapse, if the authorities do not move to save the rest of it.

The walls of Istanbul were built in the 5th century AD, and extend over an area of 22 km around the Old City. It consists of 3 sections, each of which contain 90 archaeological towers.