Some other "first ascents" could be recorded for particular mountains or routes. One is the First Winter Ascent, which is, as the name easily suggests, the first ascent made during winter season. This is most important where the climate of winter is a factor in increasing the difficulty grade of the route (higher elevation, polar latitudes). In the Northern Hemisphere conventional winter ascents are made between December 21 and March 21 and are not related to the conditions. Also in the Himalayan area, although Nepal and China's winter season permits start on December 1, the conventional winter ascents begin on December 21.