If architecture appears in your scene, all the major vanishing points (things like eaves and sidewalks) are pegged on the eye level line. Each vanishing point should be marked with a little “X” surrounded by a circle.
In the line drawing of the archway, the vanishing point is marked on the EL just beneath the circular window of the domed building. All the lines in the ceiling inside the arch and along the waterline inside the arch vanish to this point.
If you look again at the same scene, the arch is flanked by two circular columns. At the EL, the circular cross section of the columns is seen edge-on, so the bases of the columns don’t appear as ellipses. But as you go up the columns, the ellipses become slightly fuller.
So in a sense, every part of the scene is drawn with a consciousness of the eye level, even though in this scene you don’t really see a horizon.