Progress was an express train between Prague, then the capital of Czechoslovakia, and the German Democratic Republic (GDR).
Introduced in 1974, Progress went through a number of iterations, and also endured a one-year period off the rails, until it ceased running altogether in about 1990.
Initially, it was categorised as a Schnellzug, D76/77, and ran between Praha-Holešovice in Prague and Berlin-Lichtenberg in East Berlin, GDR.
In 1986, Progress was recategorised as one of the new top-of-the-line Interexpress services, and renumbered as IEx 78/79.
Progress ran as an Interexpress only until 1988, when it disappeared from the timetable.