There were two trains daily in each direction: Primera Especial (first class) and Segunda Clase (second class). The differences are important. Generally, first class trains have a restaurant and bar car, comfortable seats, tidy bathroom facilities and security, and the trip took about 13 hours one way. We found first class prices affordable, especially in view of the fact that we had come a long way just to ride the train and see the canyons.
Second class is very economical, about half the price of first class. The accommodations are not designed for comfort or viewing. It can be crowded. We understand there is no restaurant or bar car. And very importantly, the ride takes longer, about 15-16 hours.
We purchased our tickets at the station in Creel. We arrived about an hour in advance of departure, and had cash for the purchase as was suggested. Arriving early added to the fun. We met a group of Mexican tourists from Uruapan who were vacationing together to enjoy the train experience. There was a young couple from the UK, honeymooners full of life and passion about photography and each other. And a young man in his twenties introduced himself and said he had an interest in practicing English. Several of the attendants and other riders appeared to know him well as a frequent traveler. There is congeniality among those who rely on the rail line for regular transportation, as we soon discovered.