Travel by car: the driving distance between Utrecht and Mostar is about 1790 km which equals a travelling time of approximately 16 hours and 30 minutes. The recommended route goes through Austria, Slovenia and Croatia where toll fees apply while in Germany highway is free of charge.
Alternative ways of travelling from Utrecht to Mostar:
Travel by train: travelling by train is possible on this route; travel to Munich where you change the train to Zagreb and then change another train to Sarajevo. From Sarajevo there is regular train to Mostar. More information about trains in Bosnia can be found here.
Travel by plane: there are no direct flights on this route.
Map with buses from Mostar: