In 2026, the most efficient way to travel between Spanish cities is via the AVE (Alta Velocidad Española) high-speed rail network. Operated primarily by Renfe, as well as competitors like Ouigo and Iryo, these trains connect Madrid to Barcelona, Seville, and Valencia in under three hours. For regional travel, "Media Distancia" trains provide reliable service. If you are on a budget, ALSA buses offer an extensive network covering smaller towns that the rail lines miss. For very long distances, such as from Bilbao to the Canary Islands, Iberia and Vueling provide frequent domestic flights. For the best value, travelers are encouraged to book train tickets several weeks in advance, as "Básico" fares are significantly cheaper than last-minute "Premium" tickets.