Renfe Altaria is a train serive operated by locomotive pulled fixed train compositions built by the company Talgo. The trains are fixed compositions which are able to change their gauge width so that they can run on both normal and Iberian broad gauge tracks. Renfe uses them on services from Madrid to Algeciras, Alicante, Barcelona, Cádiz, Cartagena, Granada, Irún, Logroño, Murcia, Pamplona, and San Sebastián.
Picture from Barcelona Sants station 11.11.2011 by Ilkka Siissalo.

A view of the same Altaria train but from the other end, where a Siemens EuroSprinter locomotive of the class 252 was ready to pull the train towards Madrid. Altaria trains can run up to 200 km/h.
Picture from Barcelona Sants station 11.11.2011 by Ilkka Siissalo.