The University of Oxford has been given the go-ahead to construct a new Bodleian Library after a narrow vote by Oxford City Council.
Critics say the new library will ruin the view of Oxford
Councillors voted 6-5 on Wednesday to approve plans for the new £29m depository at Osney Mead, which will house eight million books.
Critics claimed the building would spoil the city's world-famous skyline.
The Bodleian Library, which stores a copy of almost every book ever printed, is full and needs more space.
An extra 5,000 are added to its catalogue each week.
The Bodleian is the main research library for the University of Oxford and occupies several sites around the city.
Its treasures include 10,000 medieval manuscripts, the papers of six prime ministers and the manuscripts of literary classics such as The Wind in the Willows.
Critics of the new building have said the "sensitive location" on a flood plain in the green belt area around Oxford would suffer.
Oxford Preservation Trust, Oxford Civic Society, Friends of North Hinksey Village and Oxford Green Belt Network submitted their reservations to the council.
English Heritage acknowledged that the building "will be visible in some mid and long range views".
But it said it would not object to the proposal if "the city council is satisfied that it has demonstrated that there are no other suitable sites available for a building of this nature".