The majority of self-driving tech testing is happening on the pristine streets of sunny California, but across the Pacific, autonomous tech developers in Russia are also working to make robot cars a reality. But in the hellish driving environments found in Moscow, that’s not an easy feat,

Silicon Valley, for one thing, offers clear weather and well-maintained roadways. In Russia, where testing is allowed in very limited circumstances right now, that won’t be the case. From The Guardian:

“We don’t have the luxury of California roads,” says Olga Uskova of Cognitive Technologies, a Russian software maker that specializes in autonomous vehicles. “The environment is ever-changing: the snow has covered traffic signs; it’s raining on your windshield, the sun is blocking you. Our people train using these kinds of data.”

Uskova asserts that technology tested in sun-drenched utopias can’t possibly translate to a city like Moscow. Gnarly road planning, terrible weather and reckless habits make the Russian capital one of the worst cities in the world for drivers.

Uskova isn’t wrong. Some automakers have lately taken to testing autonomous cars in cities that regularly face inclement weather, like Detroit, but for the most part, the development has been centered around Silicon Valley. That can’t last if autonomous cars are ever going to catch on.

So the insight from Russia is worth taking into consideration. Here’s more from The Guardian:

With roads that spread like a cobweb away from the Kremlin, disturbances like car wrecks, construction and government motorcades can wreak havoc for miles. Seat belts are scorned, and traffic laws widely ignored; speeding violations are enforced with $4 fines, paid by phone. It’s no surprise that Russia’s rate of road fatalities is nearly double that of the US, with an average of 20 serious accidents a day just in Moscow. Or, for that matter, that dashcam videos of Russian road fights and collisions make up such a popular subgenre on YouTube.

The Guardian visited a three-day “hackathon” event for driverless cars, and found that one common issue for driverless cars——tripped up some of the engineers in attendance.

Most cars struggled to identify signs, for instance, which were hard to detect in snow or rain; and for non-Russian speakers, the task was practically impossible.

“The problem is that the signs are small, and in Russia they look very similar,” explained Sami Mian, a computer scientist at Arizona State University. “The main difference is numbers and arrows, and a city entry sign can look almost the same as a stop sign. The top team had 40% accuracy.”

The story notes that car testing is limited in Moscow to a quarter-mile track outfitted with pedestrian crossings, road signs and a roundabout, so there’s still a ways to go before testing expands. But it offers relevant context for the auto industry: it’s going to be a slow crawl to expand autonomous driving across the world.