President Donald Trump says he’s changing the official name of Alaska’s — and North America’s — tallest peak from Denali back to Mount McKinley. It’s the latest chapter in a long struggle over what the mountain should be called.

Mount McKinley was officially renamed Denali in 2015, ending a century-long naming controversy. The decision was announced by then-Secretary of the Interior, Sally Jewell, citing a 1947 law allowing name changes when the U.

The Alaskan mountain, now known as Mount Denali, will revert back to its previous name Mount McKinley, which was changed by former President Barack Obama. Obama changed the name to Denali in 2015 to reflect the traditions of Alaska Natives as well as the preference of many Alaska residents.