Life is a complex problem. Consider the simple act of moving from point A to point B. Solving for that equation requires synthesizing numerous variables, like speed and obstacles. What if you make it more complicated? Like putting an unpredictable human in charge of a one-ton vehicle traveling at ever-changing speeds. Throw in some jaywalking pedestrians, rule-bending cyclists, and, the most erratic variable of all—other drivers. Drivers who are potentially distracted, potentially sleepy, potentially ragey, potentially drunk. With so much to account for, it's easy to see how it can all add up to 40,000 annual traffic fatalities in the US.

For years now, people have heralded a technological solution to this complicated problem: self-driving cars. And eight years ago, Google unleashed a pack of engineers to solve for the many, many x's. That internal project evolved into Waymo, Alphabet's self-driving car company (Alphabet is Google's parent company), and now the company is ready to show a little bit of its work. On Monday, the company gave a gaggle of 30 or so reporters a tour of Castle, its carefully-constructed self-driving car testing grounds in Atwater, California, two-hours southeast of San Francisco.

Plopped amid the brown and yellow expanse of California’s Central Valley, Atwater has been home to Waymo’s closed course testing ground since 2013. Castle takes its name from the Air Force base that once occupied this land, where the military trained World War II bomber pilots. The roads here wind their way through the 91-acre territory, intersecting, merging, forming roundabouts, connecting the low-slung, sand-colored buildings Waymo has taken over. Since moving in, the engineers have added even more complicating features: crosswalks, curbs, driveways, traffic lights, and a railroad crossing (no train), among others.

Waymo

The whole tableau isn't much to look at—a few trees, some piles of dirt and rocks, the occasional orange traffic barrier, all of it surrounded by eight-foot-high green fences that deny prying eyes—but for the engineers and test drivers who spend their days here, the scenery matters little. They’re here for the network of roads on which they can choreograph just about any driving scenario they like.

Waymo’s shiny clean autonomous minivans run pre-planned encounters with rampaging bikers, unyielding drivers, malicious potholes. The minivan handles a car cutting it off, a dopey driver pulling out of a faux driveway without looking, and a woman next to a moving truck knocking a pile of boxes into the road while another car approaches from the other direction. On more inspired days, Waymo says, its testers leap out of porta-potties into the street and hurl stacks of paper in front of their vehicles.