The Karlsruhe Pyramid is a pyramid made of red sandstone, located in the centre of the market square of Karlsruhe, Germany. It was erected in the years 1823–1825 over the vault of the city's founder, Margrave Charles III William (1679–1738). The pyramid is regarded as Karlsruhe's second emblem, the city's absolutist layout in the shape of a folding fan being the first.