This is a 3d relief map of a canyon on Mars about -7.5 lat 278 lon. It has no scientific significance that I am aware of. It just looked like a cool hike. It probably has a real name but I don't have a hiking guide to Mars so I made up my own name. I named it after Marvin the Martian's hairy sidekick. The DEM data is from http://www.mapaplanet.org/ The z-axis scale is purely speculative on my part. It looks good for a canyon, but I make no claim to it's accuracy. So please inquire locally before deciding how long a rope you will need.