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Trans-Sierra Highway Passes; Interstate 80 Donner Summit

Back in 2016 I attempted as many Trans-Sierra Highway Passes as I could upon my return to California.  I started with Interstate 80 over Donner Summit during the late winter on the way to Lake Tahoe and Virginia City.


Donner Summit is actually located north of the 7,056 foot Donner Pass.  Donner Summit has a listed height of 7,277 feet above sea level which is listed at the rest area on the eastbound lanes heading towards Truckee.






As I-80 begins to descend from Donner Summit there is an overlook of Donner Lake and Donner Pass.




US 40, the Lincoln Highway, First Trans-Continental Railroad, and the Dutch Flat & Donner Lake Railroad all crossed Donner Pass on various different alignments to the south of Donner Summit.


Previously I wrote a blog about Donner Pass which includes a history of early pioneer crossings, the Donner Party, the Dutch Flat & and Donner Road, the Lincoln Highway, and of course US 40 which can be found here:

Old US Route 40 on Donner Pass Road

Regarding Donner Summit and Interstate 80; it's construction was meant to replace US 40 and bypass Donner Pass Road.  I borrowed this excerpt from my Donner Pass Road blog regarding the construction timeline of I-80 over Donner Summit:

"Not much changed with Donner Pass Road until the Federal Aid Highway Act of 1956 which of course led to the Interstate system.  The first visual change that can be seen on the state highway map with Donner Pass Road being bypassed is in 1960 when a new stub of I-80 is shown running from the Nevada state line west past Truckee to Donner Lake.

1960 State Highway Map

The adopted routing of I-80 on Donner Summit appears on the 1961 State Highway map.

1961 State Highway Map

On the 1965 State Highway Map Donner Pass Road is shown being bypassed by I-80 via Donner Summit, but US 40 still shown as present in California.

1965 State Highway Map

It isn't until the 1967 State Highway Map that US 40 completely disappears from California.

1967 State Highway Map "

I-80 and Donner Summit are very apparent from the air.  Back in May I took some photos on a flight to Seattle which can be seen here:

Donner Pass; from 30,000 feet

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