One of the most unique landscapes in North America is to be found in Death Valley National Park, in eastern California. It’s among the hottest and driest places in USA, but the park has some amazing landscapes ranging from magnificent sand dunes, to salt pans, to colorful mineral deposits. Many areas of the park are actually below sea level.
This is definitely a place to visit in winter (from late fall to early spring). Wild flowers are in bloom. Days are pleasant although nights will be chilly (so bring a warm coat). The terrible heat of summer is extremely unpleasant, even dangerous, and best avoided. A mechanical break down of your car in July could turn into a harrowing experience.