Each of the 'rooms' is about ten feet square, the size apparently needed to support a substantial roof, and there are never external doorways. In fact, there are very rarely any doorways between the rooms, meaning that they had to be accessed from above.
You'll notice that the walls are aligned at the same angle relative to North/South, and this is the case, from what I've seen, with nearly all the many forts on the plateau with the exception of Pueblo La Plata, the furthest north. It's also the case even with forts far from the Agua Fria plateau, like the one on Polles Mesa, twenty miles to the east.
You can click on any of the images to see them larger.
Here are satellite views of several other forts on the plateau, and you can see that they all carefully follow this angle in relation to North-south.
One of the most common things to see on the plateau is what I call "crop lines" –areas where the rock covered plain was cleared in rows to allow for planting, still visible over 600 years later, and you can see quite a few in this image:
The books also talk about "terracing", and here's an example near the Baby Canyon fort:
The fort itself you can see on the small cliff-lined butte at the top of the image, casting a long shadow.
