Apple has been busy working on its electric car project at secret facilities in Silicon Valley, but the tech that will make it totally autonomous might be hiding in plain sight throughout San Francisco.

During a drive across the Golden Gate Bridge, an eagle-eyed observer spotted what could be Apple’s latest self-driving car or mapping van, a vehicle that is armed with more sensors than ever.

It doesn’t appear that the van can actually drive itself, as it had a driver and co-pilot taking measurements. There are also a couple of cameras on all four sides of the vehicle that could be used for capturing Google Street View-like photos.

Self-driving car expert Brad Templeton, who runs the RoboCarblog, told Cult of Mac that the vehicle is likely just being used for mapping data.

“It’s a mapping/street-scanning car, not a self-driving one,” Templeton told Cult of Mac. “Chances are you would use the same car for driving as mapping if doing it for a self-driving car, but it’s not impossible the data from this car could be used by a self-driving one.”

Apple has been not-so-secretly working on an electric vehicle to compete with Tesla Motors, though it’s unclear if the vehicle will come with self-driving tech out of the gate. The Apple Car certainly won’t look as ugly as a Ford Transit Van, but the company might be using the vehicle to test autonomous-driving technology.

Of course, Apple wouldn’t say if it’s the company behind the van, and the vehicle could belong to any of the numerous Silicon Valley companies exploring self-driving cars.

Have you spotted one of these vans in your city? Let us know in the comments below, or send us an email with pics.