From the Citadel in Game of Thrones to the library of Kamar-Taj in Doctor Strange, there’s been a resurgence in popular culture of ancient books chained to their shelves.

These chained libraries did exist: in the Middle Ages books were a relatively rare and therefore valuable commodity. Chaining books to shelves became the most wide-spread and effective security system in libraries across Europe.

The largest surviving chained library in the world is at Hereford Cathedral in the UK, where all the books are still kept under lock and key in their original chains. It has been rebuilt in its original arrangement, exactly as it had been from 1611 to 1841.

In this video BBC Culture explores the chained library with its librarian, Dr Rosemary Firman, getting an insight into some of the 229 medieval manuscripts still locked to its shelves and exploring how the chained library’s influence can still be felt in modern libraries today.

This is part in BBC Culture’s series taking a look at incredible libraries from around the world. Click on the video above to find out more.

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