Start with any triangle in a plane (any closed, bounded region in the plane will actually work). The canonical Sierpinski triangle uses an equilateral triangle with a base parallel to the horizontal axis (first image).
https://youtu.be/-wanF8-tUko Le triangle de Karpman, connu également sous le nom de triangle dramatique, est un triangle représentant les relations entre trois rôles d'un jeu psychologique dangereux : le Persécuteur - le Sauveur - la Victime. Comme le
Hess Triangle - The Hess triangle is a triangular tile mosaic set in a sidewalk in New York City's West Village neighborhood at the corner of Seventh Avenue and Christopher Street. Address: 110 Ave S, New York, NY 10014
Pyramids under the waters of Cuba were discovered by two scientists Paul Weinzweig and Pauline Zalitzki. They found the ruins of ancient buildings for about a mile below the sea and considered them to be Atlantis.
Nazi concentration camp badges - The Purple Triangles: "Bible Students" aka Jehovah's Witnesses who warned their German neighbors about Hitler which in turn enraged Hitler against them. Hitler fought against Jehovah God and lost