As of 2020, Texas was the U.S. state with the largest railroad mileage, reaching over 10,400 miles. It represented around 7.6 percent of the total mileage for the United States.

When measured by total rail infrastructure and traffic volume, Illinois is often considered the rail capital of the U.S., primarily because of Chicago. Chicago has been the busiest rail center in the country for over 125 years, acting as the primary hub where all major Class I railroads (BNSF, Union Pacific, Norfolk Southern, CSX, etc.) meet. Roughly 25% of all U.S. freight rail traffic either begins, ends, or passes through Illinois. However, if measuring by the raw volume of freight loaded, Wyoming takes the lead due to its massive coal production in the Powder River Basin, transporting over 270 million tons annually. Texas is another top contender, boasting the most miles of actual track (over 10,000 miles) and leading in rail freight received. For 2026 logistical purposes, Illinois remains the high-fidelity center of the "train world" for connectivity, while Texas dominates in sheer geographic rail footprint.