There are two possibilities, the direct overnight train or TGV via Irun.

    VIA PARIS-IRUN  (direct overnight train)   

There is an overnight train from Paris-Austerlitz to Vitora-Gasteiz.

Frequency:
    Paris-Vitoria: Monday, Thursday, Friday, Saturday and Sunday
    Vitoria-Paris: Wednesday, Thursday, Saturday and Sunday

Timetable:
    Paris: 19:43 Vitoria: 4:05

Price:
Age < 26 or ISIC: 100 ; 111 euros
Age >26: 126 ; 158 euros

There are discounts of 30/35% for couples travelling (not needed to be married, you can be friends, relatives or whatever, but two people) and for reservations made more than 14 days before the journey date.
For reservations and special fares see: www.elipsos.com
          

    VIA PARIS-IRUN-VITORIA (via Irun)

PARIS-IRUN

The fares are about 80 euros.

For reservations and special fares, see www.sncf.com There are discounts for advance bookings.

IRUN-VITORIA

There are different kinds of trains and different prices, we recommend you to take the cheapest ones, because there is no difference in comfortableness or time.

More info: www.renfe.es

There are also buses from Irun to Vitoria which may be cheaper than the train. See: www.alsa.es

    VIA BARCELONA

There is a daily train from Barcelona:

Barcelona-Sants                     Vitoria/Gasteiz

9:20                                         14:00

Is about 60 euros. For special fares and reservations, see www.renfe.es

    FROM CENTRAL STATION OF VITORIA-GASTEIZ  TO EJC

At the Train Station, pass the subway throw south and turn right. Continue along: Paseo de la Universidad / Unibertsitateko Ibilbidea Turn right: Frai Francisco Vitoria Ibilbidea / Paseo de Fray Francisco de Vitoria. Then turn left: Lasarteko Atea / Portal de LasarteContinue along: Frai Francisco Vitoria Ibilbidea / Paseo de Fray Francisco de VitoriaAt the roundabout, Frai Francisco Vitoria Ibilbidea, take the 1st exit. Continue along: Lasarteko Atea / Portal de Lasarte WELLCOME!

Next map shows how to arrive from Train Station (point A) to EJC (point B).