Rising from the heart of the Tularosa Basin, the glistening white sands of New Mexico form one of the world's great natural wonders. Great wave-like dunes of gypsum sand have engulfed 275 square miles of desert, creating the world's largest gypsum dunefield. White Sands National Park preserves a major portion of this unique dunefield, along with the plants and animals that live here. Temperatures at White Sands vary greatly throughout the year, with very hot summers, mild winters with cool evenings, a windy spring season, and enjoyable fall weather with mild daytime and nighttime temperatures.