The photo is a composite of many very high definition shots, and consequently there's at least one set of boots and legs missing their owner on the long stairway. And yes, the detail is amazing. Off across the river is another mysterious linear ruin - wonder what that was!

Not enough pixels! No way can I read any of the logos on folks shirts or hats.

Hunt:
From the webpage:
Why are there floating heads in the image?
http://www.gigapixelperu.com/Floating_Heads.html

For some reason I couldn't easily copy and paste the text.

If you zoom out further on the picture by using the slider you can see there is space for more pictures.

Hunt:
From the webpage:
Why are there floating heads in the image?
http://www.gigapixelperu.com/Floating_Heads.html

For some reason I couldn't easily copy and paste the text.

If you zoom out further on the picture by using the slider you can see there is space for more pictures.

There's floating heads and other artifacts in the image because it was multiple images shot with a commercially available Canon 7d, 18mgp w/400mm lens on a robot motorized gimbal mount, and then stitched together on a Mac. I count 11 images across by 6 high. Read the 'About' at the full image. The whole exposure took 1h44m. People won't stand still that long.
There's also a couple of people half sunk into the rock ledge, at about 9 o'clock position, far tower, left stairs.

Follow the stairs down from the couple half sunk in the rock and you will see a guy doing his Where's Waldo impression.