Elon Musk has a new idea brewing that leverages what has been learned in building Tesla's Autopilot system: self driving buses to dramatically reduce inner city traffic.

Tesla CEO Elon Musk

Speaking at a transportation conference in Norway, Bloomberg reports that Musk is developing a project to tackle notoriously congested cities. Said Musk:

We have an idea for something which is not exactly a bus but would solve the density problem for inner city situations. Autonomous vehicles are key. I don't want to talk too much about it. I have to be careful what I say. ... I very much agree with solving the high-density urban transport problem. There's a new type of car or vehicle that would be great for that and that'll actually take people to their final destination and not just the bus stop.

Traffic gridlock has long been a target of Musk's. One of the most prominent features of the Tesla Autopilot system is that it can manage driving in stop-and-go traffic as well as easier cruise situations. The high-speed Hyperloop transportation concept was even conjured by him while stuck in one of Los Angele's epic traffic jams.

The question is what form exactly this not-quite-a-bus self-driving mass transit system will take. There's some conjecture that the Tesla Model 3 will be the first vehicle capable of full autonomy, which would certainly go a long way to accelerating acceptance of self-driving buses. And fully automated mass transit systems already exist worldwide, although they are almost universally contained to elevated, subterranean, or restricted-access rail lines.