(CNN) It's one of the world's most beautiful cities, but Sydney's sunset was twice as spectacular Wednesday when its beaches, harbor and city skyline were framed by a rare double rainbow.

Social media was awash with breathtaking pictures, with the sight literally stopping traffic on the city's streets.

A rainbow is a natural phenomenon, formed when sunlight hits falling rain. The rain's tiny drops refract the sun's light into its individual color components and reflect it back at different angles, forming the seven colors of the rainbow. A double rainbow happens when these rays of light are refracted twice.

Science aside, there's no arguing with these amazing pictures.

Double rainbow, all the way. Our view from work today, overlooking Darling Harbour #darlingharbour #doublerainbow pic.twitter.com/BYzDMbmEKr — Nat. Maritime Museum (@ANMMuseum) June 17, 2015

Double rainbow over Manly beach (Sydney) yesterday literally stopped traffic...taken from friend's balcony. Wow! pic.twitter.com/Kl5HFXWeof — Pauline Rogers (@paulinejrogers) June 18, 2015