1989 saw the beginning of a new chapter in rail service in the Black Forest: The Deutsche Bundesbahn celebrated the creation of a new train type, called "InterRegio" ("IR"), with the introduction of new service from Konstanz via Offenburg, Karlsruhe, Heidelberg and Frankfurt am Main to Kassel. These "InterRegio" trains ran every other hour, alternating on the hour with a "Regional-Express" ("RE") train from Konstanz to Offenburg. "InterRegio" connections to Berlin, Hamburg, Lübeck, and Stralsund were offered starting in the mid-1990s.