Justin O'Beirne

Justin O'Beirne of San Francisco, California. Essays, projects, and contact information.

Surprising Changes to Google’s Cartography

Page 1 · 2 · 📍


At the zoom-levels we've looked at, the map is primarily about cities and roads.

Just look at how barren the map looks without them:

Left: Google Maps, 2016
Right: Google Maps, 2016—with all of its cities and roads removed.

Quite a difference, isn't it?

Now let's see what the map looks like with just cities and roads:

Surprising. With everything removed, other than cities and roads, the map still looks like a map.

In many ways, the map above is a simple network map: The cities are the nodes. And the roads are the paths between the nodes.


If you live in a city, you're likely quite familiar with network maps. You might even use them pretty regularly.

Here's a good example of one:

And here's an even more famous one:

One thing you'll notice about these maps: they rarely have lines that don't have any stations. And they rarely show stations that aren't connected to lines.

After all, what would be the point of a line that didn't stop anywhere? Or a station that didn't get stopped at?

And yet this is exactly what we've seen on Google Maps, both in 2010 and in 2016.

Take another look at our Bay Area maps:

Notice the pattern?

2010 - Lots of cities, but very few roads.
2016 - Lots of roads, but very few cities.

...or put another way:

2010 - Lots of stations, but very few lines(And many stations aren't connected to lines.)
2016 - Lots of lines, but very few stations(And most lines don't have any stations.)

If this was a transit map, it wouldn't be very useful.

Is it useful as a road map?


Let's take a closer look at a couple of areas within the Bay Area.

First, the Pittsburg / Antioch area:

2010 - Cities, but No Roads. Pittsburg and Antioch are shown—but how to get there? No roads are shown that go to Pittsburg and Antioch.

2016 - Roads, but No Cities. Roads leading to Pittsburg and Antioch are shown—but Pittsburg and Antioch aren’t labeled. Why travel on those roads? Where do they go?

On the 2010 map, Pittsburg and Antioch are what cartographers call "Orphan Cities". That is, they're cities that lack connections to the rest of the road network.

A similar situation exists with Santa Cruz:

2010 - Santa Cruz, but No Roads. Santa Cruz is shown, but it's orphaned (i.e., there are no roads going to it).

2016 - Roads, but No Santa Cruz. Four different roads leading into Santa Cruz are shown—but Santa Cruz isn’t.

On either map, it's not immediately clear how to travel between San Francisco (or any other Bay Area city) and Santa Cruz.

See the problem?

Both maps, the one from 2010 and the one from 2016, have a similar issue: a lack of balance.

Google Maps of 2010 had plenty of cities—but not enough roads. It was unbalanced.

Google Maps of 2016 has a surplus of roads—but not enough cities. It's also out of balance.

So what is the ideal?



*   *   *


When I was living in Chicago, I once saw an incredible map in a stationery store. Someone had taken the map and turned it into a cover for a photo album, the kind of thing you'd typically find on Etsy and other online craft sites.

I snapped a few pictures of it because it's one of the best examples of this concept I've ever seen. (The photos were taken with an iPhone 4 on a dark, winter day—so please forgive the quality.)

Now compare the map in that photo to a comparable zoom on Google Maps today:

Even though it's from the early 1960s, the old map is more balanced than the Google map.

Notice that there are no orphan cities on the old map. Every city is connected to the road network:

And not only are there no orphan cities, but there are no unnecessary roads. Nearly every road is labeled—and nearly every road has a city along it. We don't have the cluttered nest of unlabeled roads that's on the Google map. Instead, every road serves a purpose.

The balance is spot on.

And the map is incredibly efficient.


I took that picture more than five years ago, but I've always wondered what a digital version of that old map would look like. Would it be better than Google Maps today?


Let's try a quick experiment.

First, we'll take Google Maps as it is today:

Now, let's add all of the cities from the 1960s road map:

The added cities certainly improve the map's balance.

Next, let's discard all of the roads that weren't on the 1960s map. We'll keep the freeways, since many of them weren't built yet—but let's get rid of everything else:

It doesn't feel as though we're missing much with all those unlabeled roads gone. And the individual roads are now so much easier to follow, especially above Chicago. You can actually trace each one with your eyes.

Put another way: every line now has a station. And every station has a line.

There's one problem, though: we still don't have labels on most of the remaining roads.

Let's rectify that by adding most of the shield icons from the 1960s map and see what we get:

Nearly every road is now labeled, and the map is more useful.

Let's take one last look at the map we started with and compare it to the map we ended up with:

If I were lost in this area, I know which map I would want to use.


*   *   *

All things considered, I suspect that Google Maps's city reduction was an optimization for reading the maps on mobile devices, and that the new roads were added to make the maps look less empty (once the cities were removed). After all, a map with fewer labels is a map that's faster to read.

Consider that during the period between April 2010 and April 2016 (when all the screenshots were taken), sales of mobile devices exploded. This chart from Benedict Evans captures the explosion in sales:

Also consider that during the same period, mobile usage of Google Maps surpassed desktop usage.

Given these trends, it's likely that Google Maps was optimized for mobile—and this explains some of the changes we observed earlier.

Unfortunately, these optimizations appear to have only exacerbated the longstanding imbalances already in the maps. And as is often the case with cartography: less isn't more. Less is just less.

As someone who's admired Google Maps for many years, I hope that Google will consider adding a few of the cities back.



🏠 Home  ·  ✍️ Essays

Copyright © 2010–2017 Justin O’Beirne