There are other structures near this grid oddity, they can probably be explained away as massive runways (although what the hell are they flying that needs such a massive strip?). Here are the runways a little out to the grid’s east:

This is a shot from next to the runway where they look like they have loads of huge cubic packages and at the top of the frame a kind of massive bunker/bridge:

You’ll have to make your own mind up. I don’t really think it’s aliens. I want it to be aliens but I’m not a wally. This is a close up of one of the “runways”. This one looks disused:

And even closer still:

It looks like they’ve been there a while, it’s hard to say whether it’s cut into the earth, or whether it’s risen above the earth?

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