From finding passage through the Rocky Mountains, to building the 7.9-mile Cascade Tunnel, to constructing the Argentine Flyover in Kansas City, BNSF’s engineers have conquered impressive challenges in order to keep trains—and customers’ goods—safely moving. These engineering marvels also played a key role in connecting the country. Without a railroad, fledgling towns in the developing West didn’t stand a chance. Thanks to ingenuity, perseverance, manpower and machines, the railroads arrived. Towns that might have faded away prospered, many becoming bustling cities.

Today, that growth—plus demand for faster, safer and more freight rail service—creates new engineering dilemmas that BNSF is ready to tackle. Take a ride through five of BNSF’s most notable engineering wonders from the 1800’s to the present here.