Boise’s Signature Bridge: The Oregon Trail Memorial Bridge

Researched by Arts & History Staff
Boise, Idaho
Geographical Area:

The bridge and boulevard form an approach to the city which is unequaled in its stark beauty and simple grandeur by any bit of manmade highway in the west…Motorists entering Boise immediately will be struck by the panoramic view of the city before them…The visitor will be inclined to long remember the Idaho Capitol because of the first glimpse he had of the city.”


The Oregon Trail Memorial Bridge was constructed in 1931, during the heart of the Great Depression, using approximately $97,000 in federal emergency funds. It is an exquisite example of a poured concrete structure and Art Deco architecture. Morrison Knudsen Company served as the contractor; State Bridge Engineer Charles H. Kyle designed the bridge, and the Idaho Department of Public Works supervised its construction. This masterpiece 310-foot structure was completed in just over 200 days using a 100-man team working 16-hour days, seven days a week, to meet the September dedication deadline. In 2013, the City of Boise, Ada County Highway District, Idaho Heritage Trust, and private citizens joined together to restore this Boise landmark during the city’s sesquicentennial, known as BOISE 150. The bridge remains a critical structure and stately feature of the Capitol Boulevard Corridor, which links the Boise Depot to the Idaho Statehouse.

Details of the 2013 renovations

  • Architectural classification: Art Deco
  • Materials: Concrete, ceramic tile, bronze, iron
  • Areas of Significance: Engineering; Community Planning & Development
  • Built: 1931
  • Architect: Charles A. Kyle, Engineer
  • Builder: Morrison Knudsen Company
  • Renovation: 2013
  • Celebration of Renovation: October 9, 2014

Pier Lights
The original pier lights perfectly complemented the bridge design, but vandals damaged them after the 1987 bridge remodel so they were removed. The pier lights were recreated for the 2013 restoration based on an image from a 1925 mail-order catalog.

New Paint
The bridge was repainted in 2013 with a soft white color, which closely matches its original shade.

During the 1987 remodel, the original lamppost poles were replaced by poured concrete pillars, which many architectural historians deemed an inappropriate design modification. Designs for the 2013 restoration included new lamppost poles based on the original plans.

Pylon Lantern Lenses
Over the years, the original pylon lantern lenses broke and were removed. The 2013 restoration plans included replacement lenses made of shatterproof glass in colors appropriate for the original era—amber for the main lanterns and ruby for the top of the fixtures.


Image above © ISHS MS 281