What year were trains the most popular form of transportation?

Trains reached their peak popularity as a form of transportation in the late 19th and early 20th centuries, particularly from the 1870s to the 1920s. This era saw extensive railway networks being established, facilitating both passenger and freight transport across vast distances. The rise of the automobile and the development of aviation in the mid-20th century gradually diminished the dominance of trains. However, they remain a vital mode of transportation in many parts of the world today.