Eiffel tower wiki:

Tower (French: Tour Eiffel) is an iron tower built on the Champ de Mars, beside the River Seine, in Paris, France. It is the most famous French landmark and is used as a symbol of France. At the time of its construction in 1889 it was the tallest structure in the world, and remained so until 1930. Named after its designer, engineer Gustave Eiffel, it is a premier tourist destination, with over 5.5 million visitors per year.
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Pyramid wiki:

>This article is about the polyhedron pyramid (a 3-dimensional shape); for other versions including architectural Pyramids, see Pyramid (disambiguation). An n-sided pyramid is a polyhedron formed by connecting an n-sided polygonal base and a point, called the apex, by n triangular faces (nâ¥3). In other words, it is a conic solid with polygonal base. When unspecified the base is usually assumed to be square. For a triangular pyramid each face can serve as base, with the opposite vertex as apex. One of the Platonic solids, the tetrahedron, is a triangular pyramid. The square and pentagonal pyramids can also be constructed with all faces regular, and so count among the Johnson solids. All pyramids are self-dual. The volume of a pyramid is where A is the area of the base and h the height from the base to the apex. The geometric centre of a square-sided regular pyramid is located on the symmetry axis, one quarter of the way from the base to the apex.
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