BMW is teaming up with Chinese internet giant Baidu to start highly automated driving trials in Beijing and Shanghai.

BMW research vehicles capable of highly automated driving have already undergone thousands of kilometers of trials on German autobahns. The project will now be expanded to include other large cities in China, BMW said.

“BMW is embarking on a further research project which will pave the way for highly automated driving in China as well,” the automaker said in a statement on Monday. “China’s fast-expanding urban centers present the engineers with challenges such as multilevel highways.”

Prototype cars developed in this project will initially be operated on urban highways in Beijing and Shanghai.

BMW needs a partner because cars with semi-autonomous driving functions need high-resolution maps to help measure precisely when they are in danger of hitting a curb, or missing a turn.

Cars currently have insufficient memory to store detailed maps of an entire country, so automakers need to team up with telecoms and internet providers to help autonomous vehicles download detailed maps on the go.

Baidu operates China’s largest search engine and is also a provider of map services and cloud services.