“Fake” Borromean rings
On a fountain of the Castello Sforzesco in Milan, we can see this coat-of-arms. It should represent Borromean rings, but it has some crossings switched, so that the resulting knot is different. See the interactive animation Borromean and non-Borromean rings to understand the difference.
From the point of view of symmetry, it is a cyclic rosette of type C3.
foto di Paola Cereda
The image belongs to the sections...:
3. (C3) (Symmetry)
Decorations of walls and façades (Anthology of images)
Decorations of walls and façades (Symmetry)
Photos of the city (From the exhibitions of matematita)
The Sforza Castle (From the exhibitions of matematita)
Three or more components knots (Topology)
Knots in the city and outside the city (Topology)
Coat of arms, trade marks and flags (Anthology of images)