"Terrain Vague" in French means a plot of building site;

at the same time, it implies the idea of an empty lot of land with no purpose.
All cities have such places: All of us have played our secret games in empty lots as children. These areas shelter different kinds of people in different seasons, on different days; sometimes children, sometimes homeless people, sometimes lovers share them. These lots belong to all and at the same time to no one. As a no-man's land, they are mostly safe places but they may also be auspicious at times.
They are the backyards of our homes, tightly wedged secret gardens they are open to the public. No-man's land also means a strip of land between two nations to prevent people crossing the border without documents.

When I was a child, we crossed the border from Turkey to Greece at Ipsala gate through a narrow bridge. At both sides of this bridge the balustrade was painted with the colors of the two nations. The red and white color stripes of Turkey, after a certain distance, gave place to the blue and white stripes of the Greek flag. At both sides of this bridge, sunflower fields stretched. This was the no-man's land. Nobody knows who determines these places. Maybe those who use it give the place its identity. 
Testis Ear Tank Field, 2008