The primary goal is to provide a fast connection on the main trunk line between Dortmund and Cologne, located along the Ruhr Valley, with trains every quarter of an hour.

This main line has been expanded, improved or reconfigured to enable more trains to operate and at higher speeds.

For the project, 84 Siemens Desiro HC trainsets were purchased, which have higher capacity and acceleration, enabling increased punctuality.

[5] On the central section from Dortmund via Bochum, Essen, Mülheim a.d. Ruhr and Düsseldorf to Cologne four of the lines will provide an interlined service every quarter of an hour[6] and continue on from there to the following cities: The other three lines serve part of the central section, but either use parallel routes or branch off to serve the wider region.

All the lines continue outwards from the central section to connect to more cities or even neighboring states.

[17][18] The part between Duisburg main station and the border to Mülheim a. d. Ruhr is included in planning section 3, but doesn't feature exclusive tracks for the RRX.

[23] In contrast to most regional rail systems in Germany, the state of NRW tendered the trains to be used separately from the operator.

[25] The other requirements were a top speed of at least 160 km/h (100 mph), a minimum acceleration of 1.0 m/s², multiple-unit support, being bi-directional, the standard door height of 76 cm (30 in) and an existing license by the regulators.

[2][30] The contract also includes maintenance of the trains for 32 years raising the total volume to 1.7 billion Euro.

[28] Additionally to the mentioned requirements of the tender the trains feature free Wi-Fi, air conditioning, power outlets, reading lamps and folding tables at the seats and new windows that allow internet signals to pass through uninterrupted leading to a much better experience when using the internet during the train ride.