Despite massive advances in cartographic technology over the past decade, a huge number of large cities around the world remain digitally uncharted territories. Places from Dar es Salaam, Tanzania’s largest city with a population of 4.4 million, to Dhaka, Bangladesh, with a population of 15 million, lack online street maps. This isn’t just inconvenient, but dangerous: in the case of a disaster, a lack of reliable maps means aid workers have a much harder time reaching people in need.

The Missing Maps Project–a collaboration between the American and British Red Cross, Humanitarian OpenStreetMap Team, and Doctors Without Borders–aims to solve this by crowdsourcing digital maps of the entire globe, beginning with the most vulnerable places in the developing world. The organization is using OpenStreetMap as their platform, a freely available online map that anyone can edit and improve–much like a Wikipedia of maps.

Dhaka

“It’s an incredibly ambitious project,” Dale Kunce, senior geospatial engineer at the American Red Cross, tells Co.Design. “Our goal is to map as many places and people as we can. If that ends up being 100 cities over three or four years, I would be ecstatic.”

The Missing Maps Project began after Typhoon Haiyan destroyed thousands of homes in the Philippines, and a lack of digital maps of the affected areas made it more difficult for help to reach refugees. In the three days after Haiyan, more than 400 volunteers began added nearly three quarters of a million edits to a free, digital map of the affected coastal areas using OpenStreetMap technology, an effort spearheaded by the Red Cross. “After Haiyan, we realized we could crowdsource wonderful, beautiful maps of areas that had never been charted,” Kunce says. “And we wanted to map those areas before there were any disasters there.”

Crowdsourcing is at the heart of the Missing Maps Project. “It’s not us, the Red Cross, going in and mapping these communities–it’s the communities mapping the communities,” Kunce says. “The communities own these maps.” The city’s residents are the project’s number one resource. “Building a mapping community takes a little bit of effort,” Kunce says. It starts with engaging local volunteers–1 out of every 500 people in the world is a Red Cross volunteer.

Here’s how individuals map their local areas: a city must first have a “base map,” created by tracing aerial photographs of a city, which can be procured from sources like Microsoft or U.S. government agencies. OpenStreetMap software makes such tracing on your laptop simple. Once the base map trace is made, locals, whom the project calls “ground troops,” go out and about, often with paper copies of the trace, and label all of the features in a given area in their own language. Whether it’s roads, houses, or names of businesses, this data is all relevant and local. “We encourage people to basically pick a square of the city to map and go map it,” Kunce says. While city residents can do this independently, the organization is also hosting Missing Maps Parties, in which people team up in an effort to complete big chunks of a map in a short time.

Lugala

But the project isn’t just about providing better humanitarian relief–it could massively improve urban planning, transportation, infrastructure building, and crime-fighting in these previously uncharted regions.