Waymo last month announced plans to drive vehicles manually in New York for testing. Waymo said it will begin testing in Philadelphia, with a limited fleet of vehicles and human safety drivers behind the wheel.

Philadelphia is one of more than 10 cities where human autonomous-technology experts will be taking Waymos on summer “road trips,” allowing the cars “to get to know the city,” spokesperson Sandy Karp said in a statement. The testing fleets are closed to the public.