What is "alvia"

Alvia is a high-speed train in Spain used by Renfe Operadora for long-distance service with a top speed of 250 km/h. The trains have the ability to use both Iberian gauge and standard gauge, which allows them to travel on the recently constructed high-speed lines for part of the journey before switching to the ″classic″ Iberian gauge network to complete it. Trains that run exclusively on high-speed tracks are branded AVE or Avant.