Liverpool Central Library's £50m refurbishment

Manager David Stoker said staff would be filling about 40km (25 miles) of shelving

Liverpool's central library has started the painstaking task of moving rare books and documents into its new home after a £50m refurbishment.

Specialist contractors will spend the next three months transporting four million books, prints and paintings to the city's new library and repository.

The items have been held in secure storage for the last four years.

Rare treasures include the original 1207 Charter signed by King John which granted Liverpool city status.

'Salt mines'

There is also an "extremely valuable" copy of The Birds of America, by naturalist and painter John James Audubon, as well as paintings by the 19th Century artist Edward Lear.

The refurbishment has cost £50m

During the renovations, the 1850s facade of the building and historic reading rooms and specialist libraries have been restored and new facilities, including a temperature-controlled repository, have been built.

Manager David Stoker said staff would be filling about 40km (25 miles) of shelving in the new library with items, some of which are very fragile.

"These have to come in from five locations, some deep down in the salt mines in Cheshire and some from storage facilities that we have in the city," he said.

"We've also got some of the earliest examples of printing in the world, from the 1400s, from Gutenberg and from Caxton and a rare edition of the complete works printed by Kelmscott Press by William Morris," he added.

Once the move is complete and the library reopens in May, many of the works will go on permanent public display for the first time.

Such is the interest in The Birds of America it will be held in a special glass case and the pages turned just once a week.

Just 120 copes of the 1827 volume have survived, with recent auctions seeing the book selling for about £8m.