The tunnel has green and red lights that indicate whether the car should slow down or move faster. The cars have extra alignment wheels that allow it to move swiftly through the narrow tunnel.
According to the Washington Post, the project cost $40m (about R573m). Musk plans to charge commuters about a dollar for a shared ride and $4 for a private car.
After the tunnel ride, the car is elevated about 12m back to the ground.
According to CNN, Musk first thought of the idea of an underground tunnel in 2016 after being frustrated by Los Angeles’ notorious traffic.
Pretoria-born Musk said traffic congestion is getting worse ever year. “It’s like acid on the soul – it’s horrible!” he said.