For other meanings, see pyramid .
]]A pyramid is any three-dimensional polyhedron where the faces other than the base are triangular and converge on one point, called the apex. The base of a pyramid can be any polygon; it is typically a square or a triangle, leading to four or three non-base faces.A pyramid is said to be regular if its base is a regular polygon and its upper faces are congruent isosceles triangles.Cutting off the top of a pyramid, using a plane parallel to the plane of the base, leaves a frustrum of a pyramid, sometimes called a flat-topped pyramid, though it no longer satisfies the definition of a pyramid.
Pyramid-shaped structures were built by many ancient civilizations.
There are many flat-topped pyramids in China. The First Emperor of Qin (circa 221 B.C.) was buried under a large pyramid outside modern day Xi'an. In the following centuries about a dozen more Han Dynasty royals were also buried under flat-topped pyramidal earth works