In Columbus, Ohio, a group of small, autonomous shuttle buses circling downtown offers a glimpse of what some tech and transit advocates see as a key component of future urban transportation.

Operated by Michigan-based startup May Mobility, the three shuttles have been running a test route on a roughly one-mile loop around the Scioto Mile, an area adjacent to a riverfront park, since last month. Currently operating in test mode—without passengers and with a backup driver—the shuttles will begin picking up riders on December 3. Moving at a steady 15 miles per hour, these vehicles show the slow but steady progress of this technology, billed as a potential solution to transit congestion in dense downtowns.

“We want this tech to be tested in all use cases, and know we can rely on it in all weather conditions,” says Jordan Davis, director of Smart Columbus, the smart city initiative helping oversee the trial. “We don’t want to launch something that leads to false hope.”

Run in partnership with the Ohio Department of Transportation’s DriveOhio initiative, this trial is a step toward Columbus realizing its ambitions to become a proving ground for new transit technologies. In 2016, Columbus won the nationwide Smart City Challenge, a contest organized by the Department of Transportation to provide a $40 million grant to help one city invest in and test out new transit technology. Columbus’s winning proposal included three self-driving shuttles, dubbed CMAX, meant to connect residents in underserved areas to jobs.

Two years later, the new shuttles slowly running laps around the Scioto Mile loop intend to lay the groundwork for a larger autonomous transit route, one of a number of similar autonomous vehicle trials happening in cities such as Detroit and Las Vegas.

The shuttles are currently running empty to test how the technology responds to traffic, congestion, pedestrians, and driving conditions. Presenting varying traffic speeds as well as an ongoing construction project, the route, which isn’t served by any other transit service, offers a test case for the navigation system.

The Scioto Mile will serve as a public testing ground, providing free service for a year, seven days a week from 6 a.m. to 10 p.m. This high-traffic downtown area—located near offices, National Veterans Memorial and Bicentennial Park, the Center Of Science and Industry (COSI), and the new Smart Columbus Experience Center—lets curious residents and visitors test out the vehicle, and allows the city to work through traffic issues and emergency procedures before pushing the tech on neighborhoods.

Next year, the city will expand the trial and test first-mile, last-mile routes focused more on equity. Davis says the proposed routes, which will run through low-income neighborhoods, will focus on improving access. Every proposed route terminates at a site, such as a food bank, that can provide community assistance and support. Once the shuttles prove themselves as a neighborhood circulator downtown, then Columbus will explore how this new technology can help make transit more equitable.