They were known for their excellent suspension on their trucks, hence the movie Monon of the Springs.

Hah hah! From 1897 to 1956, Wikipedia says, the line operated entirely within Indiana. Then it merged.

In 1970 it operated 540 miles of road on 792 miles of track; that year it reported 1320 million ton-miles of revenue freight and zero passenger-miles.

Zero. They stopped hauling people in 1967. Today the “Monon Trail” refers to bike & walking paths created when they ripped out the rails.