Sokimex, the contractor that administers ticket concessions at Angkor Wat, has set up a bright yellow tethered balloon near Angkor Wat. 

It's certainly cheaper and more accessible than helicopter if you want to see Angkor by air. And that's useful if you want to get a fresh perspective on how it all fits together. Wish they'd paint it blue though - that would be a bit less jarring.

Angkor by air. 

Off to the left, Angkor Thom. You can clearly make out the moat and other features.

Here's a treeless corridor that may have been a road or a moat, that makes a precise corner.Lots of features like this are clearly visible by air.  Was it part of a larger square encircling the entire area? I do more administration than archaeology so I'll leave that to the experts to decide.

One of the experts. 

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