Many books in the Bodleian Libraries are kept in bookstacks (storage areas inaccessible to readers). The largest bookstack is the Book Storage Facility in Swindon which holds 8 million items.
These items will appear on SOLO with the status 'Closed Stack' and can be ordered to a library or reading room by placing a "Hold" (see: 'How do I order "closed stack" items?'). You can only order Closed Stack material to certain libraries. This includes most of the Bodleian Libraries, such as the Radcliffe Science Library, Social Sciences Library and the main Bodleian Library. Closed Stack items cannot be delivered to College libraries.
Please note that most material ordered from Closed Stacks must be read within the library and may not be taken out.