Every photo is openly licensed

The primary source is Wikimedia Commons, a media library of tens of millions of freely-usable images. The game queries it live for geotagged photographs that carry a capture date and a usable license, then filters out anything that isn't a genuine photograph — maps, diagrams, logos, and artwork are excluded. Because the query rotates across places around the world, rounds stay varied without any stored pool of images.

For date-based rounds, the game also draws on The Metropolitan Museum of Art's Open Access collection, released under Creative Commons Zero (CC0). This adds genuinely historical photographs — images from the 1800s and early 1900s that the modern, geotagged web simply doesn't contain — and widens the range of eras you'll be asked to place.

We only ever use files that are in the public domain or released under a Creative Commons license that permits reuse.

• Public domain / CC0 — no rights reserved; usable by anyone for any purpose.
• CC BY / CC BY-SA — usable with attribution to the creator.

Files that aren't license-safe are filtered out before they ever reach you.

Every round's reveal screen names the photograph, its author, and its license, with a link back to the source page. Map tiles are © OpenStreetMap contributors, styled by CARTO. If you believe an image is shown in error, please get in touch.