These are restorations of the stone portions of a cylindrical houses. These would have been topped with a conical thatched roof, though less is known about the details (e.g. pitch) of such roofs because the thatching (obviously) didn’t survive as well as the stone bases. These were located at an archeological site on the road between Cuzco and Puno.
Taken in the Summer of 2010 at Sacsayhuaman, near Cusco
Sacsayhuaman offers some phenomenal examples of Incan masonry, which used no mortar and involved perfect joints that weren’t perfectly on the horizontal or vertical (i.e. the joints had to be matched up on planes of various angles.)