Onlookers were left stunned after a rainbow gave a stunning light effect in the shape of a dome.

Footage captured in Silverton, Colorado, USA, shows the phenomenon in full effect as the light within the rainbow's arch appears brighter than that around it.

One person is heard exclaiming: "Wow! Holy mackerel!" as the camera pans across the valley showing the rainbow.

The footage was captured on August 5, 2022.