About

The idea

Every city has a shape. Not the skyline or the landmarks. The pattern its buildings make when you strip away everything else. Manhattan's grid, the rings of a medieval European town, the long sprawl of a river city, the tight courtyards of an old quarter. You have seen these patterns your whole life without ever being asked to name one.

Guess.That.City asks. You get building footprints and nothing else: no street names, no labels, no coastline, no country outline, no satellite imagery. Just the buildings, coloured in so you can read the grain of the place. From that, you work out where on Earth you are.

It turns out you know more than you think. Block size, street angle, how buildings meet the road, whether the city grew from a plan or from a thousand small decisions. These carry more information than they have any right to, and a surprising amount of it survives the trip from your eyes to a guess.

How to play

• Look at the footprints. The top map is the city, buildings only. Pan and zoom as much as you like, the whole point is to investigate.
• Drop a pin on the world map. Below it is a plain world map. Put your pin where you think the city is, then press Guess.
• Score the round. Points come from three things: how close your pin landed, how quickly you placed it, and how hard the city was. Getting the right country or failing that, the right continent pays extra, because knowing roughly where you are, still is worth something.
• Five rounds to a game. After the fifth you get a summary of the whole run.

Before each game you pick which pool the cities come from. Mixed draws on everything. Capitals is capital cities only. Casual, Hard and Genius step up the difficulty. The mode only decides which cities you meet, never what they are worth — a hard city pays the same wherever it turns up, which is what lets every mode share one leaderboard.

You can play without an account, and no sign-up is needed to start. An account gets you a place on the leaderboard, your scores and stats kept over time, badges as you go — and no ads.

Where the data comes from

The building footprints are © OpenStreetMap contributors and the Overture Maps Foundation, used under their respective licences (ODbL and CDLA). The base map on the reveal is by MapTiler. None of the shapes are drawn by hand; if a city looks odd, it is usually telling you something true about how it was mapped.

Get in touch

Found a city that looks wrong, a bug, or a boundary that has drifted? Or just want to suggest a city, say hello, or argue about scoring? Write below and it lands in my inbox. I read everything, and I answer most things.