Chaining books was commin in libraries from the middle ages onwards to stop them from getting stolen.

Hereford Cathedral's seventeenth-century Chained Library is the largest to survive with all its chains, rods and locks still working.

The famous Chained Library contains 1,500 books including 227 medieval manuscripts.

Once a year specialists and trained volunteers take six days to clean the rows of the valuable books.

The cathedral's oldest and most important book is the eighth-century Hereford Gospels.