With a game of parallel lines we built our cities at night, with tall buildings that stand out on a starry sky. A simple exercise for the 6th grade classes, with which we have experienced how easy it is to create a landscape using just some set of lines. The walls of the buildings seem almost three-dimensional, for the alternation of horizontal lines, slanting and curves. The addition of some details, such as small windows, complete our city. The drawing has been cut out and pasted on a black cardboard that creates the background. With a white pencil, finally, we have added constellations and moons.