Semana Santa
The Semana Santa (the Holy Week) is the week before Easter. Arcos, together with Seville holds the most elaborate processions in the entire South of Spain. A tradition that dates from medieval times are the processions: lifelike sculptures of biblical scenes are carried on the necks of costaleros (literally "sack men", because of the costal, a sack-like cloth that they wear over their neck, to soften the burden), and can weight up to five metric tonnes. The processioins are set up and maintained by hermandades, religious brotherhoods carrying penitential robes. The processions are very impressive to watch and they express the sincere catholic experience of the people from Arcos.
When: from the 17th until the 24th of April 2011
Feria del caballo in Jerez
Feria de Jerez, also known as Feria del Caballo (Horse Fair) is one of the most important celebrations in Jerez de la Fronter originating in the medieval ages, during one week farmers gathered to sell and buy horses, usually drinking sherry to celebrate the deals.
Nowadays it is a big celebration with streets that have tents (casetas) where you can eat, drink sherry or rebujitos and dance flamenco all night long. The feria also has an area with different rides such as roller coasters, bumper cars etc. At night time there is a sort of "roof" of pretty decorative lights lighting this little "village" like area, which allows the party to last all the way till dawn. If you visit the Feria del caballo, a traditional flamenco dress is a must.
When: From the 8th untill the 15 th of May 2011
Feria de Abril in Seville
The Seville Spring Fair, La Feria de abril de Sevilla, begins two weeks after the Semana Santa, the Easter Holy Week.  The fair runs six days, ending on the following Sunday. Each day the fiesta begins with the parade of carriages and riders, at midday, carrying Seville's leading citizens which make their way to the bullring, La Real Maestranza, where the bullfighters and breeders meet.  For the duration of the fair, the fairgrounds, a vast area on the far bank of the Guadalquivir River, are totally covered in rows of marquee tents (casetas) From around nine at night until six or seven the following morning, you will find crowds partying and dancing "Sevillanas", drinking Jerez sherry, or manzanilla wine, and eating tapas. The feria de Abril is the largest fair in the South of Spain.
When: From the 3rd to the 8th of May 2011