In two-point perspective, we draw our vertical lines, vertical. In three-point perspective, our vertical lines are at an angle, converging on our third vanishing point above or below.
The simplest way to experience third-point perspective is to stand at the corner of a tall building like a church tower and look up. Not only will the sides of the church converge to vanishing points to either side, but the parallel vertical lines of the tower will appear to converge at some point high in the sky—our third vanishing point.
Three-point perspective makes for a more realistic scene but only becomes apparent when there's enough vertical relief, either up to the sky or below, in what we're viewing. As a result, we most commonly see it in views of downtown skyscrapers, perhaps with a caped or swinging superhero.
Also see One-point perspective and Two-point perspective.
You’re welcome to use and share this image and text for non-commercial purposes with attribution. Go wild!