🔍 How we check our facts

How the check works

1. 1The text is broken down into individual verifiable claims - dates, numbers, names and superlatives such as “oldest”, “only” or “first”.
2. 2Every risky claim is verified against several independent sources: encyclopaedias, the pages of the site's custodian or the national park, academic studies and serious media.
3. 3The answer to the question is checked too, not just the story. A wrong answer is worse than a wrong story, because it punishes the player directly.
4. 4A correction goes into all eight languages at once, and is then re-checked to confirm it actually landed in every one.

How we grade what we find

• Error - the claim is untrue and has to change.
• Imprecision - the claim misleads, even if it is not outright false.
• Check on site - it cannot be settled remotely, because it depends on what a sign actually says.

Two rules we keep

• ▸A legend may appear in the text, but only labelled as a legend and only if it is genuinely well known. We never present one as an established fact.
• ▸We may point to a particular information board only where that board is documented. Where it is not, the answer has to be findable without it.

What the check turned up

• Michelangelo did not paint the Sistine Chapel ceiling lying on his back, but standing on scaffolding with his head thrown back. Our text carried the popular legend.
• The ban on women entering Karlštejn Castle is a nineteenth-century literary invention. What Charles IV forbade them in 1357 was the Chapel of the Holy Cross in the Great Tower.
• The first quarantine was introduced by Dubrovnik in 1377, and it lasted thirty days. Venice later stretched it to forty - which is where the word comes from.
• The triforium of St Vitus Cathedral holds busts of all four of Charles IV's wives, not two.