The 20th Avenue NE Bridge (also known as the Ravenna Park Bridge) is a three-hinged, steel, lattice-arched bridge that spans a ravine in Seattle, Washington, United States' Ravenna Park. It was designed by Frank M. Johnson under the direction of city engineer Arthur Dimock.[2] Built in 1913, the structure is both listed in the National Register of Historic Places and is a designated city landmark.[3][4]

20th Avenue NE Bridge
A steel-arched bridge over a wooded ravine
Coordinates47°40′19″N 122°18′21″W / 47.6719°N 122.3058°W / 47.6719; -122.3058
Other name(s)Ravenna Park Bridge
Characteristics
DesignDeck Arch
MaterialSteel
Total length354 feet (108 m)
Width18 feet (5.5 m)
Clearance below41 feet (12 m)
History
DesignerFrank M. Johnson
Engineering design byArthur Dimock
Opened1913
Closed1975 (to vehicles only)
Ravenna Park Bridge
LocationSeattle, Washington
Built1913
ArchitectFrank M. Johnson and J.R. Wood & Co
MPSHistoric Bridges/Tunnels in Washington State TR
NRHP reference No.82004246
Significant dates
Added to NRHPJuly 16, 1982
Designated SEATLJanuary 17, 1977[1]
Location
Map

The structure is 354 ft (108 m) long. It has a 250 ft (76 m) arch that rises 41 ft (12 m) over the ravine. It supports an 18 ft (5.5 m) reinforced concrete roadway. Beginning on March 11, 1975, a four-month trial began wherein the bridge was closed to vehicular traffic. The bridge did not meet the standards for arterial roads at the time, and upgrading the bridge would have been cost prohibitive.[5] The trial period was successful and the bridge has been closed to vehicle travel ever since,[6] but it is accessible by pedestrians and cyclists.[2]

References

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  1. ^ "Landmarks and Designation". City of Seattle. Archived from the original on 2013-03-06. Retrieved 2013-03-05.
  2. ^ a b Long, Priscilla (July 23, 2008). "Seattle's Ravenna Park Bridge is constructed in 1913.". HistoryLink.org Online Encyclopedia of Washington State History. Archived from the original on 2011-10-03. Retrieved March 24, 2011.
  3. ^ National Register of Historic Places; Annual Listing of Historic Properties (Part II) (PDF). National Park Service. March 1, 1983. p. 8669. Archived from the original (PDF) on November 3, 2011. Retrieved March 25, 2011.
  4. ^ "Individual Landmarks". City of Seattle Department of Neighborhoods. Archived from the original on 2010-06-04. Retrieved March 25, 2011.
  5. ^ "Ravenna Span Closing to Cars". Seattle Post-Intelligencer. 1975-03-10.
  6. ^ "Old bridge being fixed". Seattle Daily Times. 1977-01-12.