Ten years ago, paper maps were rarely current or accurate down to the meter, but over the next decade, 5G networks will enable digital maps to achieve centimeter-level accuracy, and update in real time. To that end, leading South Korean carrier SK Telecom today announced a collaboration with three Korean cities — Songdo, Yeongjong, and Cheongna — to use 5G for “HD maps” that will cover 132.9 square kilometers down to the centimeter, including lanes, road slopes, and speed limits.

While centimeter-level accurate location data isn’t conceptually new, a public-private sector commitment to maintain it on such a scale is unique. SK Telecom forged the deal with the Incheon Free Economic Zone Authority, which represents the cities surrounding the country’s award-winning Incheon International Airport. The carrier says that the maps will be updated in real time with changes including road conditions, all in the service of enabling self-driving vehicles to safely travel the roads.

SK Telecom will use its 5G Dynamic Data Platform to build and update the maps, gathering road observation data from 5G-powered advanced driver assistance systems that will be installed in public transport vehicles and government cars in the IFEZ area. Since the quantity of transmitted data will be inconceivably large, the carrier and IFEZ are building a hub to manage and analyze everything, part of a broader smart city initiative planned for the Incheon area.

“The core of 5G lies in its power to transform all industries to deliver unprecedented value to people’s daily lives,” said SK Telecom CTO Park Jin-Hyo. “We will work closely with the IFEZ Authority to accelerate IFEZ’s transition to a smart city powered by SK Telecom’s 5G network and mobility technologies.”

While current smartphones can under some circumstances send and receive location data with 3-foot accuracy, it takes an external GNSS receiver to access location services with centimeter-level accuracy. However, these receivers tend to be large and expensive, since they rely on a technology called real time kinematic processing to achieve their positional certainty. Users can sample how centimeter-level location accuracy works using modern GNSS hardware with smartphone apps, but aggregating even a single city’s worth of accurate positional data for every street — then keeping it all up to date with changes — is a monumental task.

SK Telecom has been testing 5G vehicle-related services in the “pilot city” of Hwaseong, and created a 3D HD map there last year so that two cars could simultaneously coordinate movements on open roads. At the time, the cars were each communicating at least 100 times per second over the trial 5G network, as well as sharing current road condition information, including discovery of a multi-vehicle accident. Today’s deal suggests that cellular carriers and governments may wind up having more involvement in next-generation maps than technology companies such as Google and Apple, which have thus far dominated consumer mapping solutions with lower levels of accuracy.