Symmetry is everywhere, in architecture as well as in nature it is simply gorgeous in my humble opinion. 

Symmetry (from Greek συμμετρία symmetria “agreement in dimensions, due proportion, arrangement”)[1] in everyday language refers to a sense of harmonious and beautiful proportion and balance.[2][3][a] In mathematics, “symmetry” has a more precise definition, that an object is invariant to any of various transformations; including reflectionrotation or scaling. Although these two meanings of “symmetry” can sometimes be told apart, they are related, so they are here discussed together…. information sourced from Wikipedia.org