It wasn’t long after the 1920s automobile boom that the Secret Service started carting the president around in a souped-up vehicle of his own. Franklin D. Roosevelt was the first to get an official presidential state car in 1939—a Lincoln K Sunshine Special, outfitted with a two-way radio and other bells and whistles—and the tradition has continued ever since. Though each state car is different from its predecessor, certain trends have emerged over the last 80 years.

They’ve almost all been Lincolns or Cadillacs, and colors have ranged from dark blue to black. Earlier presidents favored Lincolns; Harry Truman was chauffeured in an armored Lincoln Cosmopolitan, for example, and John F. Kennedy was riding in a convertible Lincoln Continental SS-100-X when he was assassinated in 1963. But after Ronald Reagan was given a Cadillac Fleetwood in the early 1980s, presidents began shifting away from Lincolns and toward Cadillacs (though George H.W. Bush did revert to using a Lincoln during his term from 1989 to 1993).

In fact, the only official presidential state cars that haven’t been Lincolns or Cadillacs actually aren’t cars at all—they’re buses. The Secret Service used to rent buses for the presidential motorcade, but they finally decided to manufacture their own during Barack Obama’s tenure. In 2011, they debuted Ground Force One, a 45-foot vehicular behemoth that reportedly houses oxygen tanks and even bags of spare blood in case of an emergency.

The bus may be the most formidable machine in the history of presidential vehicles, but the addition of special security features isn’t a new practice. After the attack on Pearl Harbor in 1941, the Secret Service realized the president was especially vulnerable while in transit, and agents added bulletproof tires, weapons compartments, and other safety elements to his Lincoln. A similar upgrade was made to the presidential state car after Kennedy’s assassination—this time, it was rigged with titanium armor-plated doors, reinforced glass windows, and a bulletproof roof.

Take a look at the evolution of POTUS’s wheels in the illustrations below, courtesy of UK-based vehicle leasing company Vanarama.

1. Lincoln K Sunshine Special // Franklin D. Roosevelt

The two-way radio was a big deal at the time.Vanarama

2. Lincoln Cosmopolitan // Harry Truman, Dwight D. Eisenhower, John F. Kennedy

Truman got to choose his car after he was elected in 1948.Vanarama

3. Lincoln Continental SS-100-X // John F. Kennedy

Presidential cars got safer after Kennedy's assassination in 1963.Vanarama

4. Cadillac Fleetwood // Ronald Reagan

Reagan's boxy Cadillac set a new precedent.Vanarama

5. Cadillac DeVille // George W. Bush

Bush's high-tech Cadillac even had night vision capabilities.Vanarama

6. Ground Force One // Barack Obama

This massive bus is supposed to be prepared for any kind of emergency.Vanarama

7. Cadillac “The Beast” // Donald Trump

"The Beast" is POTUS's current vehicle of choice.Vanarama

[h/t Vanarama]