You don’t want to go on a ski tour without sunglasses. The light is reflected very strongly by the white snow surface and therefore appears unpleasantly bright. The extreme UV radiation also carries a great danger of damaging the outer cornea causing “snow blindness” if the eye is exposed to the radiation over a longer period of time without protection. It is important to note that this process can also occur in cloudy or foggy conditions. There is a higher level of UV radiation at high altitudes in general because the natural absorption by the earth’s atmosphere is reduced there. While sunglasses are mainly worn during the ascent (for the descent it is definitely recommended to wear ski goggles), they still need a good fit and a firm grip. They also need sufficient lateral protection so that as little UV radiation as possible can hit the eye. The lenses should have a minimum UV protection value of 400 and a dark tint. Polarized lenses also help against quicker fatigue of the eye.