Five thousand treasures long hidden in the vaults of the British Museum go on display for the first time tomorrow in newly restored galleries that once housed the library of King George III.
The official reopening of the King's Library after a three-year, £8m restoration will be the culmination of the celebrations marking the 250th anniversary of the museum in Bloomsbury, central London.
It will house objects from the age of the Enlightenment, the great period of discovery and learning when the museum was established. A wealth of items brought to Britain by Captain Cook's Pacific voyages and curiosities including astronomical instruments from the personal collections of the museum's founder, Sir Hans Sloane, are among the highlights.
But only 20 of the books, sculptures, prints and objects - from Greek vases to stuffed birds and animals - now displayed in the Grade I listed gallery have been shown for any length of time before.
The gallery itself is the largest neo-classical interior in London, an imposing 300ft-long room in Greek revival style, built to house the library of George III after it was left to the nation by his son, George IV.
The library became the first wing of the British Museum as we know it today, eventually replacing the previous building on the site. But it has been vacant since 1998 when its books went to the new British Library.
Neil MacGregor, the museum's director, said yesterday that the new permanent exhibition in the library, entitled Enlightenment: Discovering the World in the 18th century, emphasised the founding principals of the museum in providing a free way of allowing every citizen to understand the world.
"It goes back to the origins of the museum in that [the King's Library] has the whole world in one room. That was what the museum was always about - to get the whole world in one building so everybody can try to make sense of it. The unique quality of the British Museum is it's the only building in Europe where you can do that."
During the period of Enlightenment, the public's understanding of the world moved from the analysis of texts, such as the Bible and the Classics, to understanding based on the empirical evidence of objects from the natural world, he said.
New parts of the world were being explored and archaeology, natural history and ethnography were evolving into scientific disciplines. The principal of the time, established by the mathematician Sir Isaac Newton, was that by gathering information and specimens, arranging them in a logical system and studying them, a full understanding of the world could be achieved - and that is mirrored in the new exhibition.
Andrew Burnett, his deputy director, added that most items were deliberately left without labels - although details were available - to emphasise the sense of investigation and of learning through looking. "We wanted to recapture the intellectual firmament of the time," he said.