When did the locomotive evolve to trains?

The evolution of locomotives to trains began in the early 19th century, with the introduction of steam-powered locomotives around the 1800s. The first successful steam locomotive, George Stephenson's "Locomotion No. 1," debuted in 1825, leading to the development of rail networks. By the 1830s and 1840s, these locomotives were pulling multiple carriages, effectively transforming them into trains. This marked the beginning of modern rail transportation, paving the way for the extensive railway systems we see today.