Airport barrier

There are zones that are better no to enter without a good reason or necessary documents. And in a 3D airport everywhere there are zones like this, so the 3D airport barriers were made in order to mark them. The 3D airport barrier helps the 3D airports escape the danger of becoming an overcrowded barn dividing the 3D passenger mass into well-organized lines. The 3D airport barrier is the thing that makes even uncultured 3D people civilized. Maybe this is one more reason why the 3D airport barriers are so multiple.