4. Messerschmitt KR200
The Messerschmitt KR200 is essentially an amalgam of the Reliant Robin and the BMW Isetta. Also a bubble car, this vehicle features only three wheels. The German company tasked with building this car had predominantly existed in the realm of aircraft. However, manufacturer Messerschmitt decided to construct this single-door car. As one can see, only a single person can fit comfortably within its cramped cabin.
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