By 1921, the railway was fully operational as a civil link, but operated by the military, although there were very few trains passing through, only one run every two days and during the summer period. To these were added a few freight trains, particularly it was used to transport timber of the woods. On 16 June 1921, service on the Dobbiaco, Cortina, Calalzo line officially began. Due to the heavy financial losses and the demanding work of continuous maintenance, the railway was decommissioned by the army and, in 1923, given to the Railway Commissioner of Bolzano, who gave a boost and greater regularity to the connections. Shortly afterwards, the line was electrified, but plans to make it standard gauge were not realised.
In 1956 Winter Olympics the road was closed to private traffic and most of the tourists and athletes used the railway, which reached the respectable figure of 7000 passengers per day.
When the Winter Olympics ended, passenger transport collapsed, with a preference for private motoring. Financing, investment and, above all, maintenance left something to be desired and numerous minor accidents presaged what was to be the biggest disaster in the history of this railway. On 11 March 1960, part of a convoy derailed near Acquabona (just outside Cortina) and ended up in a deep escarpment, causing two deaths and about thirty serious injuries.
The decision was made for a road link by bus.
In December 1961, the service was resumed, albeit with serious financial losses, and services officially continued until 23 March 1962, although some convoys continued to run until May 1964, when the route was decommissioned.
The section between Dobbiaco and Cortina was abandoned but maintained as it was far from the roadway, which is why we now have a route without the tracks, as the iron bridges are intact.