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Maps were generated in connection with the establishment or construction of King County roads. There are different types of road maps: engineering (design and construction), establishment, maintenance and paving, right-of-way, survey, or topographical. Unless otherwise indicated, please contact the King County Archives regarding the following map collections:

Maps and plans: Road Services Map Vault (1857- date)

This online digital collection contains full-sized hard-copy maps (survey, route, vicinity, detail, plat, topographic) of historical and contemporary county road projects, indexed by map title, road name(s), section-township-range coordinates, map date, map type, and survey number.  Please contact the King County Road Services Map and Record Center for more information about accessing this map collection. Microfilm and digital versions of the maps are maintained by the Map and Records Center, which can make full-size copies of the electronic versions of the maps. Hard-copy original drawings are held at the King County Archives.

Commissioners' Road Book No. 4 , 1876-1881

Road Book 4 (1876-1881) is a compilation of hand-drawn and hand-colored route maps, keyed to textual road establishment documents for that period. Access is by survey coordinates; some keyword access is available.

Plat reference maps, 1900-1950

These blueprint copies of plat maps were acquired and retained as a reference collection by the County Engineer's office. They are arranged in folio post-bound volumes by township and range. Annotations showing various public works projects and property actions have been penciled on the plat maps.

Survey books, 1901-1907 (approximate dates)

Between 1855 and 1907 the County Surveyor was required to execute any survey required by the county commissioners, or by any court, individual or corporation; after 1901 an index to the surveys was required to be kept.

This series consists four large volumes organized by King County range and township numbers, with one page allocated to each section within a township. On some section plans, survey lines have been marked, with relevant survey notes handwritten on the facing blank page. The surveys are of all types (for example, surveys to locate roads or lost section corners; surveys done for individuals; surveys to create lots within plats). There is a section-township-range index in each volume.

Engineer's preliminary topographic map books, 1908-1937

This series contains field maps and notes made by county surveyors documenting topography of proposed county projects. A number of surveys made at the request of individuals or groups are also present. The field maps and notes were drafts used to prepare formal survey maps. They consistently show elevations and contours along the route of, or at the site of, the proposed project. They may also contain more visual information about the natural environment (streams, vegetation, agricultural crops) and the built environment (structures, fence lines, routes of existing roads and old trains, bridges, skid roads) than is present in the perfected maps.

Other record information often present is surveyor names, survey number, survey date, and location of survey stations. They are arranged is by volume number in a roughly chronological sequence. One unnumbered volume from 1908 is present at the beginning of the series. Each volume may contain records of more than one project. An index page is present in most volumes.

Road establishment books , 1912-1936

This series is composed of bound atlases of master maps locating established county roads. Most atlases are arranged by section-township-range coordinates with each section represented by one map. Road numbers are usually present on the maps. Books in this series include:

· [Road establishment atlas,"TxN RxE," approximately 1874-1909]

· King County Highway Plat Book #1, 1890

· King County Engineer: Existing County Roads, 1912-1917

· Road establishment book, 1913

· King Co. Engineer road establishment atlas, ranges 5 and 6, 1931

· King County Engineer road establishment maps, ranges 7 and 8, 1930

State highway plans, 1925-1933

After 1900, Washington counties worked increasingly with the state Highway Department to maintain roads built with state funds. The Highway Department sent reference copies of its highway plans to the counties. These plans are for State Highway #1 (Pacific Highway, through Auburn, Kent, Des Moines, Seattle, and via North Trunk Highway to the Snohomish County line) and State Highway #2 (Sunset Highway, over Snoqualmie Pass).

Volume 1 is for grading both highways, and there is one volume each per highway for concrete paving. In addition to construction details, the plans provide information about the land to either side of the right-of-way: property owner's names, location of structures such as barns and sheds, wetlands, pastures, cultivated fields, etc. The brittle blueprint pages have been reinforced with pasted paper. Maps on each page have been indexed by section-township-range coordinates.

Secondary road project files, 1935-1938

This series includes specifications, plans, maps, correspondence and other contract documents relating to County road maintenance and construction projects. Also included are applications for Federal government grants. Most of these Depression-era projects were funded by the Federal Emergency Administration of Public Works (PWA) or the Works Progress Administration (WPA).

State highway plats, 1959-1972

This series is composed of county copies (blueprint and blueline) of Washington State Department of Highways plat maps showing extent of rights of way for state highway projects. Included are detailed (large-scale in some instances) mapping of areas, including location of buildings, immediately adjacent to or inside right of way, including path of the Seattle Freeway (Interstate 5).

For more information about the above records, please contact the Archives.

TTY Relay 711

Monday, Tuesday, Thursday, and Friday: 9 am-4 pm

Please note the Archives is closed Wednesdays.