System for the secondary suspension of a superstructure (1) of a rail vehicle, having a hydropneumatic spring unit (3), with an assigned suspension accumulator (7) as an active spring element, placed between the superstructure (1) and a bogie (2) arranged below it, which active spring element ensures at least one raised travelling level (NF) for the superstructure during the travel of the rail vehicle, in which case, by way of the hydropneumatic spring unit (3), by means of a level control, in addition to the raised travelling level (NF), a lowered station platform level (NB) for the superstructure (1) can also be adjusted, the suspension accumulator (7) being blockable when the rail vehicle is stopped in order to relieve the level control during a change of load, and in that, for an emergency operation caused by a pressure drop, additionally at least one emergency spring cylinder (18) is provided which, in the event of a pressure failure, by means of an independent moving-out, ensures an emergency spring level (NN) situated between the station platform level (NB) and the travelling level (NF).