Perfect Shapes in Higher Dimensions
The Platonic solids have been known since antiquity. It has been suggested that certain carved stone balls created by the late Neolithic people of Scotland represent these shapes; however, these balls have rounded knobs rather than being polyhedral, the numbers of knobs frequently differed from the numbers of vertices of the Platonic solids, there is no ball whose knobs match the 20 vertices of the dodecahedron, and the arrangement of the knobs was not always symmetric.
Learn more : https://en.wikipedia.org/wiki/Regular_polytope
In this Video Carlo Sequin talks through platonic solids and regular polytopes in higher dimensions.