After looking through some images of the Great Wall of Peru, I thought I'd go back and look at the Great Wall of China to note similarities, if any, that I find. I noticed that it appears that the fortified side of the Great Wall was facing China, which strategically make no sense. You have on side with crenellations (think Castle Walls) and the other has just a normal knee wall. The side with the crenels should face outward, to provide protection and strategic advantage. I would make sense to challenge the thought of China building this as a defensive fortification, versus it being built by the people occupying the opposite side, which I believe would have been Tartary.
Anyone have any insight on this?
The short answer is no. The long answer is nooooo.
Unfortunately, the notion that 'Tartary' existed as a centralised state entity is utter hogwash originating in anti-Catholic conspiracy theories peddled by Russian nationalists during and after the breakup of the Soviet Union. I wrote a post about this over on /r/badhistory a few months back, and I'll warn you that the tone is a bit glib and sarcastic, but the core points stand on their own merits. I'll also confess to mishandling a couple of aspects of the follow-up conversation as well, but again, the core points stand.
As for what the 'Great Wall' was (scare quotes because the term was not contemporaneous to the Ming, but came about during the Qing period when it had ceased to have military utility), I cover that in this answer regarding walls before the Ming, and this answer which also covers those early walls, as well as explains the rationale behind the Ming walls (which are the ones that survive today).