It’s easy to overlook the fact that we stand on the “shoulders of giants” (attributed to Sir Isaac Newton, 1675), but in the last eight months, Donner Summit has received national recognition from three very different organizations. This article discusses the background and significance of these milestones.

California Beginnings

To understand Donner Summit’s role in history, let’s start with why California was important enough to warrant international attention. Between 1821 and 1847, Alta California was a territory of Mexico. During this period, the British eyed it as an expansion to their Hudson Bay Trading Company operations in Oregon, while the Russians hunted for furs as far south as Fort Ross, California. At the same time, following the success of the Lewis and Clark expedition and the annexation of Texas in 1845, the idea of Manifest Destiny gained momentum in Washington, D.C. Manifest Destiny was the belief that the United States was divinely ordained to expand across North America, promoting democracy and progress.

With the Treaty of Guadalupe Hidalgo in 1848, California became a U.S. territory and then gold was discovered! California quickly became a global destination. People, mostly men, came from everywhere to make their fortunes. Europeans, Central and South Americans, Australians, Chinese, and Americans from the East Coast all flocked to the area. Many stayed and California’s population grew rapidly. It became a state in 1850, and by 1860, its population had soared to approximately 380,000.

The Railroad Era Begins

Given California’s distance from the commercial and political centers of the East Coast, there was a strong case for building the first transcontinental railroad. In 1862, while the Civil War raged, President Abraham Lincoln signed the Pacific Railway Act to unite the country east to west, even as the war split

it south to north. The Act set up a race between two railway companies: one departing from Council Bluffs, Iowa, and the other from Sacramento. The companies would meet near the 32nd parallel, and the more track a company laid, the more money and land it would receive from the U.S. government.

The Race was On!

The route proposed by civil engineer Theodore Judah was chosen for the Central Pacific Railroad – climbing eastward out of Sacramento, up and over the Sierra at Donner Pass. Judah was a brilliant civil engineer who came to California at age 28 in 1854 to build the first railroad west of the Mississippi. His plans called for 15 tunnels to minimize the slope of the tracks. Because this was a race, it required a massive labor force and the best “modern” equipment available.

In the 1860s, a labor shortage existed, as most local workers were busy mining their own claims or were being paid high wages to work in the Comstock Mines of Virginia City, Nevada. In early 1865, Charles Crocker, head of construction for the Central Pacific, experimented with using Chinese labor. The experiment was a success and the Chinese workforce grew to approximately 12,000 men.

To excavate cuts and fills for the rail base, workers used picks, shovels, wheelbarrows, and black powder. When they reached Donner Summit and began work on the longest tunnel yet constructed for a railroad (Tunnel 6), crews used four-foot-long drills (chisels) struck with two-hand sledgehammers (double jacks). The drills created holes in the granite, which were then packed with black powder and detonated. This worked, but it was slow.

In 1846, Ascanio Sobrero of Turin, Italy, had invented nitroglycerin, a new, much more powerful explosive. Alfred Nobel later developed a blasting cap to control it and eventually created dynamite. In February 1867, nitroglycerin was tested in Tunnel 6. The tests proved successful and excavation speed improved by 54% to 72%. Due to its instability, nitroglycerin was manufactured nearby in a lab and handled exclusively by specially trained Chinese crews. Despite some mishaps, only one fatality was attributed to nitroglycerin of an Irish foreman.

To quote a paper of the time regarding the highway for the Iron Horse (the railroad):

“The grandest highway created for the march of commerce and civilization around the globe.” Daily Alta California, June 20, 1868

National Recognition

To honor these achievements from the 1860s, three national plaques have been or will soon be installed around Donner Summit.

The first plaque, already in place at the Lampson-Cashion Hub (intersection of the Pacific Crest Trail and Donner Pass Road), comes from the National Railway Historical Society. It honors the ingenuity of the engineers, the laborers of the railway, and the achievement of conquering the Sierra.

In December 2024, the National Park Service recognized the Chinese railroad workers by designating two of their work camps near the tracks as a National Historic Landmark: Summit Camp. The placement and dedication of the plaque are still being finalized and will likely occur this summer.

The third plaque, created by the American Society of Civil Engineers, recognizes the first use of nitroglycerin in constructing a railroad tunnel. Nitroglycerin, later stabilized as dynamite, became foundational to commercial blasting applications. It was from these patents that Alfred Nobel made his fortune, which now funds the Nobel Prizes.

Additional Information

On Tuesday, July 8, a presentation titled National Recognition Comes to Donner Summit will be held at the Truckee Tahoe Airport. The event will be in the Community Room and will begin at 6:00 p.m. The presentation is free, though donations are appreciated.

More information is available from the plaque originators and the Donner Summit Historical Society, the Truckee-Donner Historical Society, and the Museum of Truckee History.

About the Author

Dave DePuy is a retired electrical engineer who worked for Silicon Valley startups until 2015. He now resides and volunteers in Truckee, California, with his wife, Judy, and their dog, Morticia.