There are many local public holidays in this part of Spain & I was interested to find out more about the origins of Dia de la vieja. The following information has been taken from many sources; therefore, I cannot ensure its accuracy.
The holiday is said to date from the seventeenth century.
The Church in those years was strict during Lent, and wanted to replicate the forty days and forty nights that Jesus was in the wilderness and the harshness of those days.
The Franciscans proposed holding a day where there was no fasting (and quite the opposite); a day of abundant food, before Lent is started and hence the expression of the ‘old’.
It takes place on Thursday before Lent and is a day for families to picnic, eating typical local products like tortilla, paella, small cakes, cod & rice pudding.
The ‘old’ is represented partly by the above religious history & partly by a pagan figure ‘Old’ (represented by an old woman muñeca/doll).
The dolls are made of coloured paper, with a dress, apron and a scarf on their heads. The head is covered with cloth & decorated (it contains numerous ‘goodies’ such as sweets – I guess similar to piñatas).
Once the feasting has finished, the ‘doll’ is placed at a distance of about 6 meters or so and people throw stones until it is totally destroyed and you can get the goodies inside.
Often, they are blown up by a rocket (firework). Seeing an ‘old lady’ blown up on the beach is slightly strange, but the locals have great fun.
It is believed that the first village where this was held was in Almeria, in Cuevas del Almanzora , where the Franciscans arrived in 1651.
There are scholars who also believe that the ‘old’ is rooted in Pagan spring festivals celebrated in ancient Mediterranean civilizations: Etruscans, Greeks and Romans.
Also, according to others, the “day old” relates to the first day of the waning moon of spring.
If you know more about the origins, I would love to know, so please leave some feedback.