As the nation marks Donald J. Trump’s inauguration as the 47th President of the United States, it’s a good opportunity to note one of his most trusted companions: the Presidential limousine. Affectionately known as “The Beast,” the President’s limo is a custom-built, highly secure fortress on wheels that proudly wears the Cadillac crest.

Presidents have been riding in Cadillacs for more than a century. In 1919, President Woodrow Wilson rode in a Series 53 1916 Cadillac limousine during a parade in Boston to celebrate the end of World War I. (Cars from other manufacturers have also served presidents over the years; the first Commander in Chief to ride in a motor car was William McKinley, who reportedly rode in a Stanley Motor Carriage steam car on July 13, 1901.)

Two Cadillac convertibles – dubbed the “Queen Mary” and “Queen Elizabeth,” named after the great ocean liners – served Presidents Roosevelt, Truman, and Eisenhower. First used in 1938, the 21.5-foot, 7,660-pound vehicles were equipped with a full ammunition arsenal, two-way radios, and heavy-duty generators.

Cadillacs were also used to transport Presidents Reagan (a Fleetwood) and Clinton (a Fleetwood Brougham.)

The term “The Beast” was first used in 2001, in reference to the limo used by President George W. Bush. Unlike its predecessors, this one was custom-built, designed, and engineered by a research and development team at General Motors. GM designed the vehicle to the exacting standards of the U.S. Secret Service while maintaining signature design cues from the Cadillac DeVille.

A re-engineered version of the Beast, code-named “Cadillac One,” and featuring design cues from the Cadillac DTS, debuted in 2009 to transport President Obama. The current version, modeled after the Cadillac CT6 debuted in 2018 during a trip by President Trump to New York City.

The Trump family has long had an affinity for the Cadillac brand, according to the new President himself. In a speech last September in Macomb County, Michigan, just outside Detroit, he was asked about his “all-time favorite car,” and in responding to the question he talked about how much his father Fred Trump liked Cadillacs.

“I learned so much from him, and he loved Cadillac,” he said, according to the Detroit Free Press. “I mean, his biggest luxury in life was to get a brand new, dark blue Cadillac every two years. And he would. He would get that car, he said, ‘Look at this car.’ He didn’t know about a Rolls Royce. All he liked was Cadillac, and I love it. I think it’s a great car.”