The Cologne–Frankfurt high-speed rail line is a 180-kilometre-long (110 mi) railway line in Germany, connecting the cities of Cologne and Frankfurt. Its route follows the Bundesautobahn 3 for the greater part, and currently the travel time is about 62 minutes. The line's grades of up to four percent require trains with a high power-to-weight ratio which is currently only met by third-generation and fourth-generation Intercity-Express trains, with the latter operating at reduced speeds. It was constructed between 1995 and 2002 at a total cost of six billion Euro according to Deutsche Bahn.

Frankfurt am Main Airport long-distance station is a railway station at Frankfurt Airport in Frankfurt, Germany. It is served by long-distance trains, mostly ICE services running on the Cologne–Frankfurt high-speed rail line. It is the largest railway station serving an airport in Germany with about 23,000 passengers each day. The station is served by 210 long-distance trains daily, of which 185 are Intercity-Expresses. It and Limburg Süd station are the only railway stations in Germany that are served exclusively by long-distance trains.