Hi, the Hirise project take very high res photos of the Mars surface (home page: http://hirise.lpl.arizona.edu/).
Color dots are zones that were photographed. You can see that there are almost no pictures in the "forbidden zone". This zone contains a number of strange "formations", similar to forests and lakes (!), and it seems that people at Hirise accurately avoid it .

if you want to give a look to these unusual features on Mars, you can visit: http://mmmgroup.altervista.org/e-trees.html
where there are medium-res photos taken by another NASA probe, named MOC.

A "lake" on Mars (photo MOC m0901354, 2.75m/pixel):