Based on a painting of the same name by R.B. Kitaj, If not, not was the largest tapestry in the world when it was created by the Master Weavers of Dovecot Studios in 1997, requiring 113 kilos of wool and 7,000 person hours to complete.

The artwork brings together tragedy, beauty, literature and art onto one single tapestry – providing a symbolic glimpse into the wealth of information stored in the British Library. For example, you can see:

• T S Eliot depicted, bottom left, wearing a hearing aid, with scenes of destruction from his poem The Waste Land around him
• idyllic landscapes inspired by the paintings of Italian artists Giorgione and Jacopo Bassano
• palm trees in a shaft of light, top right, referring to Joseph Conrad’s novel Heart of Darkness
• a sculptural head turned on its side, on the left of the tapestry, being one of Matisse’s heads of Jeannette
• a red building at the top, nestled in trees, which is in fact the gatehouse to Auschwitz – a detail inspired by the artist’s realisation that the railway line to the concentration camp passed through some particularly scenic countryside.

So why did architect Sir Colin St. John Wilson commission this apocalyptic work for the Library?

A library is made up of all kinds of memories – both beautiful and distressing. This artwork unites these memories together to reveal the complex subject matters tucked away in our walls, which visitors can encounter for themselves as soon as they enter a Reading Room or one of our exhibitions.

Originally hanging on the opposite wall, where the large exhibition poster currently resides, the tapestry also functioned as a noise barrier to absorb some of the hustle and bustle that greets visitors as they enter the Entrance Hall.

Love it or loathe it, the artwork forms an integral part of the building’s architectural design, so won’t be getting replaced any time soon.

Hear more about what Wilson had to say about the artwork in this interview extract. You can also hear the full interview with him, recorded as part of National Life Stories' Architects' Lives oral history programme.

This artwork (shelfmark BLWA 4) was funded by the Arts Council of England Lottery Fund, the Bute Charitable trust, William Grant & Sons Ltd, Ruth Robertson and Ninian Crichton Stuart.

How is the tapestry cleaned?

15 years after the artwork was installed, it began to display visible surface dust. Measuring 7 metres squared and weighing 113kg though, where to start with cleaning such a huge tapestry?

The tapestry was taken down and rolled before being taken away for intense conservation cleaning. Using a hoover, the optimum level of suction was determined and the entire front and back surfaces were cleaned using a low powered vacuum suction.

The bag of dust has been retained by Collection Care staff for further scientific analysis. We are very serious when it comes to dust.

During the clean, casings from carpet beetle larvae and degraded moth cases were also removed. To ensure that no insects or eggs remained, the tapestry was placed in a freezer at -18°C for two weeks.

The tapestry was then re-hung on the wall using industrial strength Velcro, specially designed to take the weight of such a heavy item.

Read our blog for more details about the cleaning of the tapestry.