- Indian Mounds Regional Park (Saint Paul, Minnesota) (Wikipedia)
Indian Mounds Regional Park is a public park in Saint Paul, Minnesota, United States, featuring six burial mounds overlooking the Mississippi River. The oldest mounds were constructed about 2,500 years ago by local Indigenous people linked to the Archaic period, who may have been inspired by the burial style known as the Hopewell Tradition. Mdewakanton Dakota people are also known to have interred their dead here well into that period. At least 31 mounds were destroyed by development in the late 19th century. This burial mound group includes the tallest mounds constructed by people Indigenous to Minnesota and Wisconsin (except for the unique 45-foot (14 m) Grand Mound outside International Falls, Minnesota). Indian Mounds Regional Park is a component of the Mississippi National River and Recreation Area, a unit of the National Park System…
- Archimedean solid (Wikipedia)
In geometry, an Archimedean solid is one of 13 convex polyhedra whose faces are regular polygons and whose vertices are all symmetric to each other. They were first enumerated by Archimedes. They belong to the class of convex uniform polyhedra, the convex polyhedra with regular faces and symmetric vertices, which is divided into the Archimedean solids, the five Platonic solids (each with only one type of polygon face), and the two infinite families of prisms and antiprisms. The pseudorhombicuboctahedron is an extra polyhedron with regular faces and congruent vertices, but it is not generally counted as an Archimedean solid because it is not vertex-transitive. An even larger class than the convex uniform polyhedra is the Johnson solids, whose regular polygonal faces do not need to meet in identical vertices.