Standard gauge railroads use a track width of 4 feet 8.5 inches (1,435 mm), which is the most widely used rail gauge in the world. This uniformity allows for easier movement of trains across different regions and countries, facilitating trade and travel. The standard gauge was established in the early 19th century and has become the benchmark for rail systems, including those in the United States, Europe, and Asia. Its adoption has contributed to the efficiency and interoperability of rail networks, making it a crucial element in the development of modern transportation.