Photo of the "Wall" in High Def!
Kaguya (Slene)took this High Definition picture as it orbited the Moon. You can view some other JAXA High Def pictures at this Link. They show some of the best detailed shots of seas, craters and mountains I have ever seen. There are hundreds of remarkable craters and mountains on the moon to observe. One feature that I go back and observe each month is a favorite: Rupes Recta ( the Straight Wall). It captures the dark shadow along the slope of the fault. A closer view shows a ramp and debris along the wall. A close up photo of that dark line that we can see just after first quarter.
This description is from Wikispaces.com
Sometimes called "the railroad," is a remarkable and almost unique formation on the E. side of Birt, extending for about 65 miles from N.W. to S.E. in a nearly straight line, terminating on the south at a very peculiar mountain group, the shape of which has been compared to a stag's horn, but which perhaps more closely resembles a sword-handle,--the wall representing the blade. When examined under suitable conditions, the latter is seen to be slightly curved, the S. half bending to the east, and the remainder the opposite way. The formation is not a ridge, but is clearly due to a sudden change in the level of the surface, and thus has the outward characteristics of a "fault" Along the upper edge of this gigantic cliff (which, though measures differ, cannot be anywhere much less than 500 feet high) I have seen at different times many small craterlets and mounds. Near its N. end is a large crater, and on the E. is a row of hillocks, running at right angles to the cliff. No observer should fail to examine the wall under a setting sun when the nearly perpendicular W. face of the cliff is brilliantly illuminated.
Another description is at the LPOD