Making of Maps: Ground Truth glue

The final post in our Making of Maps series shows you how Ground Truth brings all the pieces of Google Maps together. Catch up on posts 1, 2, & 3 for more info! — Ed.

Henman Hill or Murray Mound? For years, British tennis fans have argued over the proper name for this hill near Wimbledon. Recently, this quirky debate over naming rights made its way to Google Maps, as people used our Map Maker tool to wrestle over the knoll’s identity. Never fear, tennis fans: whichever name you prefer, you’ll be sent to the right location when you look it up on Google Maps—let’s call it deuce.

Making sure you get to the right place, no matter what name you know it by, is just the sort of thing our Ground Truth team handles every day. Ground Truth’s aim is to keep Google Maps as up to date and accurate as possible, whether that means considering user reports from Map Maker and Report a Problem or proactively looking for new changes ourselves. Every day we start by scoping out what’s happening in the world—and by using algorithms and a little elbow grease, we can identify what roads will close for Labor Day, what housing developments are opening in Texas, and which street names are changing in Denmark (note: there are a lot of them). Ground Truth gives us the ability to use all this information to shape the map—so we can include colloquial street names, newly opened businesses, and even indoor floor plans.

All the streets in Sondergarden, Denmark were renamed this year as part of a country-wide initiative to make addresses easier to understand

Another way Ground Truth keeps Google Maps accurate is through imagery; and if a picture is worth a thousand words, you can imagine how useful satellite, aerial, and Street View imagery imagery can be. With a bird’s-eye view, we can trace the roads running through a town or identify bodies of water and park boundaries throughout a region. (One of my favorite projects is using satellite images to add golf courses to the map, including green spaces, trails, and each hole on the course.)

Satellite and aerial images are used to trace roads, bodies of water, and more (St. Petersburg, Russia)

With Street View, we can also add the granular detail needed to give you good directions. Intersections become easy to navigate because we can tell which direction each lane will take you; points of interest are easy to find because we can add information that can only be seen from the street, like the name of a restaurant or building address. Combine this with the fact that our Street View cars are designed to pinpoint exactly where each photo was taken, and the map starts to look like a mirror of the real world. 

Street View images can help pinpoint businesses and determine lane directions (Brașov, Romania)

Ground Truth takes information from thousands of sources—governments, imagery, organizations, individuals—and makes it into one cohesive map. But the best part of putting together this giant puzzle is how it helps people every day. It can save you time, empower you to get things done, and give you the opportunity to travel and explore without worry. Reaching our 50th Ground Truth country was an important moment for this project, but it’s far from the end. As long as the world keeps changing, we’ll keep mapping.

Posted by Nick Volmar, Program Manager & Ground Truth Operator