I do not believe we are looking at walled structures, only a landscape created by natural geology, however, the geology shows some interesting anomalies, such the as the indentation (lower right) that looks like a rock has been removed, plus the mounds of mud like structures middle right (not to mention the obvious trail (s).
The quality of the grainy image is again very poor (a copy of a copy I feel), so close up detail is not good.....Sol 1935
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"Creating a fiction when stating a fact destroys the credibility of the truth one are trying to convey"
The website that I got the original I was playing with is one that claims to make the colour as near to human eyesight as possible. If you go to their website (in the link) you can read about how it is obtained from the NASA black and white photographs taken through different wavelength filters and then reconstructed.
The thing is, our colours are only so green on earth because our plant life is based on chlorophyl. The plants on another planet might do it in a different way or use different wavelengths to produce their energy to run their biological systems.