The connection from Wiesbaden to the new line was planned under various options for the Cologne-Rhine/Main high-speed line under discussion during the 1980s. Only in the case of a purely left-bank route (to the west of the
Rhine) was a link not provided to Wiesbaden. The Hessian state government considered that a remote link to the Wiesbaden would be inadequate. The forecasts in the 1990s were that more than 1,000 passengers a day would use high-speed services to Wiesbaden. The (ultimately realised) right bank route between
Cologne and
Frankfurt along the A 3 initially provided for a connection from
Niedernhausen to Wiesbaden Central Station. This required the construction of an 11 kilometre long tunnel between the northern edge of the city and the station. This option was originally analysed with a maximum grade of 2.5 percent, which was subsequently increased to 4 percent. The city of Wiesbaden suggested that the continuation of the route to Frankfurt be abandoned and that all trains run via Wiesbaden Central Station and from there run on existing (partially upgraded) lines.
Deutsche Bundesbahn (DB) examined numerous route options between the Niedernhausen-Wiesbaden Central Station route and a corridor between Niedernhausen and Wiesbaden Cross (along the A 3). Primary emphasis was placed on a grade of up to 4.0 percent. A variant developed at this time envisaged, for example, the building of a station between
Bierstadt and Erbenheim, east of the settlement of Hainerberg. South of Erbenheim station there would be a branch line. Geological studies showed significant geological problems with a route running under Bierstadt and the
Salzbach valley. DB then distanced itself from such variations, looking for geologically favourable solutions, even if they required trains to reverse in the central station. At the demand of the U.S. military, part of the route was shifted 15 metres to the north (away from the Wiesbaden Army Airfield). In addition, at the end of 1996, the U.S. military required that the control tower be able to stop the train traffic next to the airport. An agreement at the beginning of 1977 envisaged that the control tower would control a signal controlling the approach of trains. During the planning, the construction of a previously agreed by-pass road around Wallau was considered for inclusion in the project.
DBBauProjekt, which had already been commissioned to design the new line, was also contracted to design the road and to implement the first stage of the bypass. Initially it was planned to build the line as a single-track and at a later stage to build the second track. In mid-1998, it was announced that the connecting curve would be constructed with two tracks and opened at the same time as the Cologne-Rhine/Main high-speed line. With the commissioning of the high-speed line there would initially be a regular interval
Intercity-Express (ICE) service from Wiesbaden and later, if there was a sufficient volume of traffic, two services. The estimated additional cost of the second track amounted to 12 million
Deutschmarks (about €6 million). In the 1990s, two pairs of trains per hour were planned for the connection to Wiesbaden. From mid-1998 only one hourly train pair was planned. The reason was low estimated traffic demand.
Operations near
Wiesbaden-Erbenheim, running towards Wiesbaden The number of trains running on the Breckenheim–Wiesbaden line has been reduced in several stages since the opening of the line. At the beginning of operations in December 2002, eight pairs of ICE services per day ran between Wiesbaden and Mainz, in the 2005 timetable it was reduced to five and from June 2006 to four. From December 2007, three pairs of trains running via Wiesbaden remained. DB runs said that the low passenger numbers was the reason for the cuts. In autumn 2008, the ICE services running between Cologne and Wiesbaden were, according to
Deutsche Bahn, occupied by an average of 88 passengers. They were thus to be the least loaded ICE trains operated by DB. The trains carry more than 440 seats. Since the timetable change in December 2008, two pairs of service remain, running only from Monday to Friday. ==Engineering==