As part of the planning for the Cologne-Frankfurt high-speed line, ways of connecting high-speed trains on the line to the airport were investigated. Originally, the regional station was to be expanded as part of the new line project with a fourth track. Despite the high cost of the reconstruction of the existing station it was forecast that the capacity would not be sufficient in the medium term. Another proposal considered was to build an additional station in the existing building. Although a feasibility study found that would have had positive returns, this option was rejected due to its high cost. The board of the former Deutsche Bundesbahn decided in April 1990 to build an above ground long-distance station. If there was sufficient traffic demand, the new station would also serve regional traffic from the south.