President Donald Trump signed numerous executive orders on his first day in office on Monday—one of the executive orders was to rename Mt. Denali and the Gulf of Mexico.

In one of his first acts as president, Donald Trump used an executive order on Monday to rename the Gulf of Mexico and Denali in Alaska. To start, Trump re-named the Gulf of Mexico the “Gulf of America,” following through on a promise he made during his campaign. The body of water borders Texas, Louisiana, Mississippi, Alabama, and Florida.

President Donald Trump renamed the Gulf of Mexico to the Gulf of America and the Alaska mountain Denali to Mount McKinley. What you need to know.