There’s a real buzz in the air about flying cars right now. Various automakers have invested money in vertical mobility projects and Hyundai’s North American CEO recently claimed air taxis would be ready for customer flights as early as 2025.

But wind back six decades and certain people were getting excited about a very different type of dual-role car, specifically one that doubled as a boat.

The German-built Amphicar 770 was the brainchild of Hans Trippel, who had been building amphibious vehicles since the 1930s and created the Trippel SG6 Schwimmwagen used by German forces during WWII.

It was launched, so to speak, in 1961 and right from the beginning Trippel believed America would be the biggest market. That’s pretty clear from the fins and chrome rear end, though the extreme departure angle necessary to climb up slipways out of the water means the nose has more in common with a Jeep than a Cadillac.

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Power came from a rear-mounted 1147cc Triumph four-cylinder engine developing 47 bhp. It drives the rear wheels through a four-speed gearbox for road use, and drives two propellers when in water. Bizarrely, you steered it the same way in both environments, the car turning using the angle of the wheels in water and not via a traditional rudder.

The 770 name comes from its ability to do 7 mph on the water and 70 mph on land, which means it wasn’t that great at being a car or a boat. That, and the fact that almost nobody needs a car that’s also a boat ensured sales were modest. Fewer than 4,000 Amphicars found homes between 1961 and 1968 against predictions of more than 20,000. One home it did find, though, was President Lyndon Johnson’s Texas ranch.

The Amphicar might have flopped when new, but they’re pretty collectable today. This one is up for auction with Bonhams on August 13 in Carmel, California where it’s estimated to make between $40,000-50,000. It’s described as ‘a beautiful example’ but the listing suggest the next owner might want to give it a water-tight checkup before dropping it into the drink.

The idea that Trippel found financial backing (from Herbert Quandt of BMW fame, no less) to put the Amphicar into mass production seems crazy, but the 770 certainly isn’t the wackiest amphibious vehicle we’ve come across. Back in 2016 we reported on an sea-going Lamborghini Countach replica, and even that’s nowhere near as insane as Rinspeed’s submersible Lotus Elise.