Building the Impossible
Grade 4 California history lesson on the engineering challenges of building the Transcontinental Railroad through the Sierra Nevada, from Pengi Social Studies Chapter 5. Students learn how Chinese immigrant workers blasted tunnels through granite mountains in harsh winter conditions to complete the impossible Central Pacific route.
Key Concepts
Building the Transcontinental Railroad was an engineering nightmare.
While the Union Pacific built quickly across the flat Great Plains, the Central Pacific faced the Sierra Nevada wall. They had to carve roadbeds out of sheer granite cliffs and blast 15 tunnels through solid rock. In winter, snowdrifts reached 40 feet high, forcing them to build miles of wooden snow sheds just to keep working.
Common Questions
Why was building the Transcontinental Railroad so difficult?
While the Union Pacific built quickly across flat Great Plains, the Central Pacific faced the Sierra Nevada mountains. Workers had to carve roadbeds from granite cliffs, blast 15 tunnels through solid rock, and work in extreme winter snowstorms.
Who built the Central Pacific portion of the railroad?
Chinese immigrants made up about 90% of the Central Pacific workforce. They did the most dangerous jobs, including drilling into granite cliffs and setting explosive charges while suspended in baskets.
What engineering problems did railroad builders face in the Sierra Nevada?
Engineers had to find routes through mountain passes, blast tunnels through solid granite using black powder and nitroglycerin, remove massive amounts of rock, and construct tracks stable enough to handle heavy trains in freezing temperatures.
When was the Transcontinental Railroad completed?
The Transcontinental Railroad was completed on May 10, 1869, at Promontory Summit in Utah, when the Central Pacific and Union Pacific railroads were joined with a golden spike, connecting the country from coast to coast.