Mitchell Point Tunnel

[1] It was built in 1915 and opened late in the year, the first major roadway tunnel in the United States.

[3][4] In 1932, the Toothrock Tunnel was opened, and some traffic was rerouted to the new alignment,[5] though Mitchell Point Tunnel remained open to vehicle traffic until the early 1950s, when the road was rerouted to the base of Mitchell Point.

[1] The tunnel was subsequently blocked off with debris, and remained closed until 1966 when it was destroyed as part of Interstate 80N construction.

[1] As part of the rebuilding of the Columbia River Highway into a network of trails, the Oregon Department of Transportation has considered the possibility of boring a new tunnel on Mitchell Point.

[8] In 2021 the Oregon Department of Transportation (ODOT) announced commencement of a project to build a replica tunnel in the original location.

Inside the tunnel
Looking up from the river
Entrance to the tunnel
"The Most Costly Road in the World" "Mitchell's Point Cut on Columbia Expensive Piece of Highway Engineering" July, 1915 article (part 1)
"The Most Costly Road in the World" "Mitchell's Point Cut on Columbia Expensive Piece of Highway Engineering" July, 1915 article (part 2)