The development of the steam locomotive in the early 19th century transformed the world, carrying people and goods at unprecedented speeds around the globe. America's first steam-powered railroad—the Baltimore & Ohio—opened in 1830, and within decades hundreds of thousands of railway miles crisscrossed the nation. Today, 182 years later, the descendants of those first railroads—including CSX Transportation—continue to play a key role in our lives, moving millions of carloads of freight each year. From the earliest steam locomotives to today’s high-speed “bullet trains,” here are eight things you may not know about the “iron horse.”