The highest mountain in the United States of America is Mount Denali in Alaska. It peaks at 20,310 feet high, or 6,190 meters. It is located in the center of Denali National Park and Reserve. A lot of the various national parks in the United States center around a certain landmark - the Yellowstone geysers, Denali mountain, etc. The official, formal name for the mountain from 1896 to 2015 was Mount McKinley.
It was named such by a gold prospector in support of the United States President, William McKinley. However, most of the natives of Alaska had already been calling it Denali at that point, and continued to do so despite the official government name. In 2015, the US government changed the official name from Mount McKinley to Denali.