The highest mountain in the United States is Mount McKinley in the Alaskan Mountain Range. Its elevation stands at 20,236 feet. The highest mountain summit in the contiguous United States is Mount Whitney which has an elevation of 14,505 feet.
The longest mountain range in the United States is the Rocky Mountains. Not only is this mountain range the longest in the United States, but at over 3,000 miles in length it's the longest mountain range in the world.
The Alps are the largest mountain range found on the European continent. The Himalayas are the highest mountain range in the world and are located in Asia. The Appalachians of North America are the oldest mountain range in the United States.