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In this photo from April 1965, Lyndon Johnson took two visitors to his Stonewall, Texas, ranch on a ride in his Amphicar. A West German firm built 3,770 of these land-to-water vehicles between 1960 and 1968, and the president loved his lagoon-blue model.

According to one of LBJ’s aides, Joseph A. Califano Jr., the president liked to play a trick on visitors. Califano first encountered the Amphicar when he visited the ranch and LBJ offered him a ride. “We reached a steep incline at the edge of the lake and the car started rolling rapidly toward the water,” Califano recalled. “The president shouted, ‘The brakes don’t work! The brakes won’t hold! We’re going in! We’re going under! ’”

The Los Angeles Times tested an Amphicar in 1963 and reported that the transition from highway to lake was fairly easy: “There is no trick to handling it, on land or sea.” The process was simple. One: drive the car into the water. Two: engage the two propellers, located under the rear engine compartment. Three: Steer as usual—the wheels acted as stabilizers.

Despite these initial favorable reviews, the Amphicar never quite took off. As automotive critic Dan Neil wrote in Time in 2007, the car’s flotation was “entirely dependent on whether [its] bilge pump could keep up with the leakage.”

There’s still an international Amphicar Club, which holds periodic “swim-ins” where the assembled owners take to the water to the delight of spectators. This year’s swim-in calendar can be found here.