Isa Lake Bridge, Spanning Isa Lake at Grand Loop Road, Lake, Teton County, WY

The first road from Old Faithful to West Thumb was completed in 1892 and passed Isa Lake. 

In the 1930’s planning began for improvement of the route and the plan included a crossing of Isa Lake. Originally a culvert was initially going to be used for the crossing but the crossing design evolved into a low timber bridge “to preserve the natural existing conditions as near as possible.”

 Construction began on the route in 1941 and the bridge was completed in July 1942 but the complete route was not completed until after World War II. 

The eight-span bridge has a total length of 160 feet. The bridge deck has a width of 28 feet with guardrails of 14-inch diameter logs.

 

Isa Lake Bridge typifies the early design philosophy of the National Park Service, which was to use indigenous materials to harmonize man-made features with their natural surroundings.

According to the 1905 book, The Origin of Certain Place Names in the United States, the lake was “named for Miss Isabel Jelke, of Cincinnati,” though any reason as to why has been lost to history. 

Isa Lake is acknowledged to be the only natural lake in the world that drains to two oceans

https://www.atlasobscura.com/places/isa-lake

https://www.loc.gov/resource/hhh.wy0183.photos/?sp=3

https://www.waymarking.com/waymarks/WMDPF5_Isa_Lake_Bridge_Grand_Loop_Road_Wyoming