Have these been identified?

I have a vague memory of seeing someone (somewhere) explain these crude land forms (this one is a triangle) but I can't for the life of me remember where: zoom.earth/#view=21.416339,-11.228703,19z

There's other shapes as well, squarish ones and so forth.  This happened to be one in a discussion.  My first thought was animal pens but it doesn't explain the circles embedded in the structure (or does it?)

Perhaps tomorrow I can check this on my PC - answer within a week I cannot guarantee.

Some kind of forts..? Notice, there are multiple similar structures around... Animal pens also could be a reliable theory and what if both? I can imagine a horsemen stronghold with such defensive structure (triangle with bastions)... (?)


GE(web) link

Thanks for interesting spotting!

Meanwhile you can do a try browsing my stuff (check my signature) or do a search for threads by siggi or archaeo .

Welcome around!

G

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Edit: have checked - nothing in my files, but found this:

These are seem to be French (colonial) forts - check this libreddit thread with map and photo  references for other spottings of such triangular forts with exactly the same inner (and outer) structures.
(the same thread on reddit) 

Of course 'style' as it was built and dimensions are quite different by your spotting so still we must not be fully satisfied! 

Luck, we have further Africa experts around (I call chriss and tafrawti) who may have the most trustworthy infos when the Sahara comes up. 

Do you happen to have other examples? 

...

Ah genius!

Forts, indeed.  And no, I don't have other examples.  Someone was asking me about them and I thought I'd check with experts.