Durham University Library manages the archives of Durham Cathedral.
Durham Cathedral Library, in the cathedral cloister, looks after the printed and other manuscript collections held by the cathedral (including the medieval book manuscripts)
List of Cathedral Library collections and catalogues available online
During building work in the cathedral cloisters (from spring 2014) the library premises are not accessible and the library service is being run from the adjacent 5 The College site. See http://www.durhamcathedral.co.uk/learning/the-cathedral-library/opening-hours-and-access for current information. Most collections are temporarily housed at 5 The College but some are at Palace Green Library, so it is recommended that you check availability and location before planning a visit.
For general information about Durham Cathedral see their website http://www.durhamcathedral.co.uk/
For information about visiting Durham Cathedral Library see http://www.durhamcathedral.co.uk/learning/the-cathedral-library