The biggest fiesta in Spain is the annual Romeria de El Rocio in Huelva, South of Spain. Hundreds of thousands from mostly southern parts of the country going on a pilgrimage to the church of El Rocio. What a blast! Another spanish fiesta take place at the easter holiday. The rowing regatta in Donostia in September, Feria de Abril in Sevilla and so on. I found the spanish people know to party the best.
All images by ©Arthur F. Selbach