From its website, "The Special Collections Division is the Libraries' major resource for rare and archival materials covering a broad range of topics, formats, and periods. Research strengths include the history of the Pacific Northwest, Alaska and Western Canada; architecture; book arts; 19th century American literature; photography; and historical children's literature. Special Collections also houses the official Archives of the University of Washington."
You may find their hours here, http://www.lib.washington.edu/about/hours/special.
Some useful information from its website is listed here,
"All collections are non-circulating. Except for some reference resources on open shelves, all materials are housed in secure, non-browsing stacks and are retrieved for users upon request.
Most collections are available at all hours of opening; however, manuscript and University Archives materials are not available on Saturdays and holidays. The majority of materials are stored on-site and can be retrieved quickly. Some manuscript and archival materials stored off-site are retrieved on a set schedule. Advanced planning is needed to see these items.
A small portion of the collections have donor imposed or legal restrictions. Access to manuscript collections is governed by terms agreed to by the donor of the records and the Libraries at the time of the gift. Most accessions are available for public use, but some may only be used by advanced academic researchers or are subject to other restrictions. University Archives collections are open to the public, subject to the terms and conditions established by transfer agreements or deeds of gift. Please note, however, that many collections of university records contain temporarily non-public material that are restricted to use only by University officials. "
For each of your visit, "you will be asked to fill out a registration card at our Reception Desk. The first time you come, you must provide your full name, address, and phone number. All visitors are asked to fill out a registration card, no matter how brief their visit. People who accompany you into Special Collections but do not use any collection materials must also register. After signing in, you will be given a user number, which you should keep with you during your visit. This number is used on retrieval forms and helps staff match you with requested materials. After you sign in, you must check all of your belongings into a locker with the following exceptions. You may bring loose paper, pencils, and laptop computers without cases into the Reference Area. If silenced, cell phones are permitted. You may bring cameras without cases into the Reference Area, but you must first check with Reference Desk staff before taking any photographs. You will be given a locker number corresponding to your user number. Liquids cannot be stored in lockers unless secured in spill-proof containers."
For more information on visiting the collection, please visit here, http://www.lib.washington.edu/specialcoll/general/use.html read more