A hole in the ground with 2 point perspective

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.