Question

what region rainbow colourfull​

Answer 1

Just take a trip down to the Rainbow Mountain in Peru. Vinicunca, also called Montaña de Siete Colores (Mountain of Seven Colors), is located in the Andes in the Cusco region of Peru. In order to get to the trailhead, it's a three-hour drive from Cusco.

Answer 2

"Ranbows" appears is Seven Colours because,,Water droplets break Sunlight into the seven colours of the Spectram.YOU get the same results When, Sunlight passes through a Prism.The water Droplets in the atmosphere act as prisms,though the traces of light are very Complex..

hope it helps ✌✌