One of the best known of the huge walled plains, Clavius is the second largest crater on the nearside. Despite its striking appearance it is, like all walled plains, a very flat feature. In fact, an observer standing at its centre would be unable to see its walls at all as they would all be below the horizon.
Photo: Steve Massey. The full size original of this and other astro video camera images may be seen on his Astronomy Page.