This train, which does a notoriously long journey over conventional lines, is often loaded in the timetable system shortly ahead. Check on renfe.com as there is some delay before it appears on DB.

Last summer had to book regular tickets for this train as I saw seats were running out (and I absolutely needed it for my trip from Valencia to Alcázar de San Juan), since seat reservations for Spain can mostly only be obtained in Spain. This might be the case around easter too.

To be fair, there are direct AVE's from Córdoba to Barcelona which are considerably faster, and I wouldn’t say the Torre del Oro is particularly spectacular - maybe just the Despeñaperros pass. The high speed line between Córdoba and Barcelona also has quite nice scenery.