Guide for Hiking the Donner Pass Summit Railroad Tunnels
Hike through five historic old Donner Pass railroad tunnels blasted out of the granite by the Chinese workers of the Central Pacific Railroad during the construction of the transcontinental railroad
It’s a unique experience hiking through up to five of the historic old Donner Pass railroad tunnels that were hand-blasted out of the granite by the Chinese workers employed by the Central Pacific Railroad during the construction of the transcontinental railroad.
The tunnels were in use for 125 years but were abandoned when a new route with a 10,000-foot tunnel was constructed straight through Judah Mountain just a bit south of here in 1993.
The tunnels consist of various lengths and combinations of a rock-blasted tunnel section with concrete snow sheds on each entrance to the tunnels. Most people make no distinction between the snow sheds and the actual excavated portions but the differences are obvious once you are inside.
While the excavated sections are bored through the rock, the snow sheds were added to the openings to extend the protection from avalanches. You will notice the differences immediately as the snow sheds have vertical slots cut into them to allow light into the tunnel.
Between the tunnels are various open areas with nice views over Donner Pass, Donner Lake, and Donner Summit Bridge.
From Highway 80, from the East take exit 180 to Donner Lake Road to Donner Pass Road, from the West take exit 174 to Donner Pass Road. Just to the west of Sugar Bowl Road look for the large parking area on the south side of Donner Pass Road at ( 39.316524, -120.330799 ).
A flashlight or headlamp for the tunnels is a very good idea
The tunnels are wet and can be muddy, but you can avoid the puddles
Most people only explore the first couple of tunnels, so the further you go the fewer people you will see
A tripod would be good to take long exposures to create bracketed HDR images due to the extreme dynamic range of the dark tunnels versus the bright light coming through the entrances
You can hand-hold a lot of interesting shots with good camera stabilization
A flash or light to fill in details in the tunnel walls and ceilings is helpful
1-5 miles total out and back depending on how far you go
This pass through the Sierra Mountains sits at 7000 feet and has been in use for thousands of years, beginning with indigenous people who left their marks through petroglyphs on the rocks near the tunnels. Settlers used the pass on the arduous journey to California, driving their wagons or sometimes dismantling them and carrying them over the pass.
When the Transcontinental Railroad was proposed in 1862, they looked for a path across the Sierras, they too chose Donner Pass for the route. Theodore Judah surveyed and laid out the route, and hundreds of Chinese workers began the back-breaking work in May 1865 of blasting the 15 tunnels and laying the railroad bed and tracks. The pass is one of the snowiest in the United States, getting an average of 34 feet of snow so working conditions were extreme.
The projects were completed in June 1868. All of the tunneling was done by hand drilling the thousands of 2 feet deep holes to be filled with black powder and nitroglycerin.
The new transcontinental railroad shortened the six-month overland trip from the Missouri River to California by wagon to just seven days and was known as Track #1. One of the more unique locomotives was designed as a result of traversing the pass, the unique 2-8-8-2 “Cab Forward”, looked like a backward locomotive with the cab on the front of the design instead of the back, which kept the crews away from the thick smoke and dangerous gases that would build up in the tunnels and snow sheds.
I have purposefully chosen not to promote the well-known graffiti in the tunnels. While there are a handful of well-done, highly talented images you will find, the vast majority of the graffiti, I would wager around 99.99% of it is just amateurish, ugly and untalented. I don’t feel the need to promote people’s need for “artistic expression” in the guise of defacing a historical place.
From the parking area, you can see the entrance to Tunnel 6 just to the east of you. You walk under the underpass for Sugar Bowl Road and the entrance to Tunnel 6 is right behind it.
Tunnel 6 (aka the Summit Tunnel)
This is the most famous of the tunnels with the most interesting history. Its rock-blasted section is the longest at 1659 feet. It is 16 feet wide, and originally 19 feet tall. The Chinese workers started drilling and blasting from both ends and in both directions from the middle via an access shaft from above. Progress averaged 14 inches a day with the best day advancing just 27 inches.
They started in September 1866 and finished in August of 1867 working 24hrs a day, 6 days a week. If it looks taller than 19 feet that is because the bottom was dug out to increase the clearance for modern trains. During the year of construction, there were 44 winter storms dropping over 30 feet of snow. The workers had to dig tunnels through the snow from their work sheds and quarters to the tunnel openings.
As soon as you exit tunnel 6 tunnel 7 is immediately in front of you, there is about 500 ft of flat open space between them. You can see the Donner pass summit bridge to your left.
Tunnel 7 seems to have been constructed as an open slot through the rock that they then roofed over the top making it technically a snow shed instead of a true tunnel. The rock-blasted section is about 100 feet in length but the snow sheds on both ends triple that distance.
As soon as you exit tunnel 7 you can see tunnel 8 about a thousand feet away. But first, look off to your left, if you look down you should be able to see a path coming up from the Donner Pass Road, this is another popular entrance to the tunnel system hike. This is a good short diversion to take to see some petroglyphs left by the Indians on the flat rocks below.
Petroglyphs ( 39.317150, -120.320809 )
To see the artwork, head off the track bed to your left, follow the trail going down, and look for the big stone interpretive marker at the rock art site. The artwork is thought to be possibly up to 1000 years old created by the ancient Washo people. This pass was a travel corridor to and from Lake Tahoe then as it is today, the pass was likely a gathering place. Look for numerous faint shapes of lines, circles and zigzags.
The Chinese Walls ( 39.315538, -120.320124 )
Looking back up to tunnels 7 & 8 you are getting a good view of the Chinese Walls. This term refers to any of the dry-fit stone walls the Chinese workers carefully built on this section of the railroad. The 75-foot long lower wall was built to fill in the ravine between the tunnels and support the track bed, while the upper wall supports the mountainside above Tunnel #8’s entrance and helped act as a snow block.
Head back up to the track bed and the entrance to tunnel 8. On the way enjoy the nice view of Donner Lake.
The underpass is part of the old Lincoln Highway AKA the Old Donner Summit road, at one time drivers had to drive onto the tracks for a short distance, the underpass was eventually added for safety.
Tunnel 8’s rock-blasted section is about 375 feet long, but with the snow shed portion on the east end, this is by far the longest tunnel, running about 3/4 of a mile long. If you are a fan of graffiti Tunnel 8 is the place to see it, there are large concentrations of it throughout and especially toward the middle of the tunnel.
You enter from the west via the short portion of the snow shed and then enter the short rock-blasted section, and then continue on for the seemingly never-ending east-side concrete snow shed. You won’t see light at the end of this tunnel for quite a while, due to the length of the tunnel and that it curves around the mountainside. All of the concrete snow sheds you see on this hike were once built of wood but were eventually torn down and rebuilt in concrete. As you continue through the long snow shed section there are vertical slots cut in the concrete wall to allow in light. You can start to notice that on your right is the actual mountainside and how after blasting out the rock wall and the track bed they covered this with the left wall and roof of the snow shed to protect this entire section of the track from avalanches.
This picture is a good representation of what the wooden snow sheds looked like originally. The wooden snow sheds were engineered to hold up to 60 feet of snow from an avalanche and were often built of 20-inch timbers 4 feet apart from local Truckee pine and fir. By the 1950s, most of the wooden ones had been replaced with concrete.
There are a couple of large openings in the wall of the snowshed where you can walk out to vistas and viewpoints. When you start to reach the opposite end there’s another large section of Chinese wall of granite blocks put together with great skill on your right side.
Exiting Tunnel 8 there’s about a 200ft section of open space with views and then you’re standing in front of tunnel 9 and its snow shed entrance.
From Tunnel 10 you can look back and see the long snow shed of Tunnel 8 hugging the side of the mountain
Tunnel 9 is a lot like tunnel 8 except a much smaller version. You will repeat the same experience, with a smaller blasted section in the middle and the concrete snow sheds in the beginning and the end again.
Exiting Tunnel 9 to the long open section before Tunnel 10.
Tunnel 10 repeats itself much like Tunnels 8 & 9. Tunnel 10 mimics the length of Tunnel 8 with the entire structure running for just under 1/2 mile. The interior curves quite a bit as it wraps its way around the bend and the mountain completing a 180-degree turn. If you go all the way through Tunnel 10 you’ve gone about 2.5 miles one way, there isn’t much to see after Tunnel 10 so most people who have made it this far would turn around and head back.