The northern lights are an unusual phenomenon that can be observed in the Arctic Circle. The colorful light visible in the night sky is actually a solar wind, or a stream of charged particles moving along the Earth's magnetic field. Depending on the intensity of proton and electron emission by the Sun, the aurora adopts different colors: blue, green, red or white. To admire the spectacular arches and waves of the northern lights, it is worth visiting cold Lapland. In some tourist towns there are even special igloo houses with glass ceilings, thanks to them guests can stare at the bright sky for hours.