This is an interesting building with 3 trapezoidal windows, located near the hill where the Sacred Plaza lies. It is 11 m long and 8 m wide.
It has no roof and doesn’t show sign that it has ever had any.
The Temple of the Tree Windows is a Wayrana-type temple (or Huayrana), this means that is has only 3 walls, built with rectangular stones. In the temple, there are 7 trapeze-shaped niches on the central wall and 5 on each side of the wall.
The Temple of the Three Windows is a relatively simple structure, perhaps it wasn’t finished.
Some specialists speculate over the fact that certain buildings seem unfinished, because the inhabitants of Machu Picchu have left in a rush.
The rope fence blocks visitors from running around wildly and putting their heads out the three windows. These fences are everywhere in Machu Picchu to protect the archaeological values from the destructive effect of tourist flocks.
The view from up there is spectacular, you can stare towards the lower parts of the city, admire the buildings from above.
A good place for taking photos from, indeed.