The technology and engineering in the Megacity have been swirling around Munich for nearly 20 years.
In 1991 BMW showed its first electrically driven city car concept. The E1 hatchback was powered by a rear-mounted electric motor with a claimed range of 130 miles.
This was followed up by the Z13, a three-seat city car concept based on an aluminium spaceframe and driven by a rear-mounted 80bhp petrol engine. The Z13 had a central driving position.
BMW used a rear-engined layout and carbon-reinforced plastics (CRP) in the 1999 Z22 concept. It was designed to offer the interior space of a 5-series Touring in the length of a 3-series, and rode on a wheelbase as long as a 7-series.
Building the car out of CRP ensured the Z22 was around 550kg lighter than a contemporary 528i Touring (at around 1100kg), and it was twice as fuel-efficient. BMW engineers claimed that they could extract almost V8 performance from a 134bhp motor.
However, the Z22 also featured a drive-by-wire control system for the steering and brakes, as well as a head-up display, active headlights and a prototype iDrive system. BMW registered 61 patents as part of the Z22 project.