See how I sketch some city block, using 3 vanishing points.
Notice how I start by using a straight horizontal line where I place the two fist vanishing point, this line represents the height of "my eyes." Bellow this line I later on draw a curved line representing the horizon, this helps create the illusion of being high up from the ground.
I was actually planning on creating a 3 point perspective drawing, but it seams like I just wasn't quite finished playing around with the 2 point drawings yet. So I had to make this hole in the ground first.
I guess I will move on to the 3 point perspective tomorrow then. And that's when we get to see the world trough the ayes of superman or a frog.