Niagara Falls rendered more spectacular by rare rainbow

Somewhere over this rainbow sits Niagara Falls, and it is literally perfect.

A Canadian man dining with one of the most spectacular views in the world has captured a rainbow in the shape of a rare perfect circle.

The man was eating at the Skylon Tower Revolving Restaurant overlooking Niagara Falls last week when the phenomenon happened.

Instead of the usual arc seen from ground level, the 230m elevation revealed the rainbow in its full unbroken glory.

Rainbows are formed when sunlight and raindrops collide at a certain angle, separating the usually white beam of sunlight into seven colours.

They can only be seen when the sun shines on the drops from behind the viewer.