Pyramid

The King's Chamber inside the Great Pyramid has two small openings, both rectangular in shape, one in the north wall and the other opposite in the south wall. Each penetrates horizontally the solid interior of the pyramid, built using hundreds of thousands of limestone blocks weighing between one and two tonnes a piece. They then climb at an angle due north and due south respectively, before coming close to exiting the pyramid's corresponding exterior faces.
Two similar "air shafts"
exist in the Queen's Chamber positioned directly beneath the King's Chamber. These also were found to climb at angles within the monument's superstructure toward the exterior walls of the pyramid.