The former Deutsche Bundesbahn (DB) began planning for a network of high-speed lines for both passenger and freight trains in the 1960s.

The 1973 federal transport plan included a high-speed line between Cologne and Groß-Gerau (near Frankfurt), as well as between Hanover and Würzburg and between Mannheim and Stuttgart.

The second federal transport plan in 1985 (which was drawn up when the first TGV line had been operating for four years) included a passenger train-only railway, which meant that much steeper grades would be acceptable.

The technical standards adopted were: DB negotiated with the states of North Rhine-Westphalia, Rhineland-Palatinate and Hesse over the route.

Each state had objections to the bypassing of the cities on the Rhine, particularly Bonn, Andernach, Koblenz, Mainz and Wiesbaden and four other routes were examined that passed through some of these.

No agreement was reached and the Federal Cabinet agreed on 20 December 1989 to a recommendation of the Transport Minister to adopt the A3 route and, among other things, to include a station at Limburg.

Although the route as set out above was adopted under the federal railway development law on 15 November 1993, the last legal challenge to the project was not resolved until September 1998.

The opening of the whole route, which had originally been planned for 1999, took place after numerous court challenges and geological problems, at the end of July 2002.

[9] In the same month the first trips with diesel locomotives were run to adjust the height of the overhead electric lines on the southern section.

[10] During construction, traffic on the neighbouring A3 was significantly affected and up to 48 building sites with a reduced maximum speed of 100 km/h (60 mph) were operating simultaneously on the autobahn.

[9] The symbolic opening of the line took place on 25 July 2002 with a special train carrying approximately 700 honoured guests.

The HSL follows the Siegstrecke to the rebuilt Siegburg/Bonn station and then heads south to run through the Siegauen Tunnel under the Sieg.