The FCAB operates freight trains on the line that goes to Argentina through Socompa Pass. On the Argentina side, there is no traffic except the famous tourist train "Tren de Las Nubes" (Train of the Clouds). On the Chilean side, the FCAB trains serve the 2 copper mines Zaldivar and Escondida with branches that connect with the main line about 198 km east of Antofagasta (via La Negra and O'Higgins). This means that the west / Chilean part of the line sees no traffic on the last 131 km, which is of course the most spectacular section
The picture shows a typical freight train serving the copper mines. It has tank cars carrying sulfuric acid and empty flat cars that carry the finished product – plates made of highly purified copper – returning empty from the sea port storage facilities to the mines.