Patron Saint Fiestas of San Bartolomé (St Bartholomew)
San Bartolomé's biggest celebration of the year honours patron St Bartholomew, building over August to the feast day on the 24th. Expect open-air concerts, folklore and traditional Canarian sports, a religious procession, street theatre and fireworks.
San Bartolomé spends most of August building up to its big day, and the programme is wonderfully old-fashioned in the best way. Evenings fill the plazas with concerts that swing from rock bands to Canarian parrandas, while quieter corners host card tournaments, chess and Canarian bowls played with genuine local seriousness. There's a comedy night, street theatre, and inflatables and workshops to keep children busy.
The romería is the heart of it: a folk pilgrimage that sets off from the football ground and winds up to the church square, with traditional offerings carried along. On the 24th the patron's day brings a solemn procession behind the municipal band. Things wind down with a final street parade, a midnight fireworks display and a verbena dance that runs late. Most of it is free, and you'll be welcome to wander in.
Source: https://turismolanzarote.com/en/event/fiestas-patronales-de-san-bartolome/