You are in the train station (estacion de tren) of a spanish speaking place and you need to ask at what time is the train leaving, this is the right way to say it:

-A que hora sale el tren?
(What time does the train leave?)

-A que hora sale el tren para Madrid?
(What time does the train to Madrid leave?)

You can change the word 'tren' (train) for other travel vehicles:
el autobus (the bus)
el camion (the bus, Mexico)
el avion (the airplane)