Catalan authorities decided to launch the campaign following two complaints from women who were told they should cover up their breasts at public pools. Authorities declined to reveal more details about the cases.
"We wanted to try to combat the discrimination that women suffer sometimes when they go topless in some situations like swimming pools. Women should have the right to freedom of expression with their bodies," Neus Pociello, executive director for the Catalan Women's Institute, which is part of the regional government, told The Telegraph.
"This discrimination stems from the sexualisation of women's bodies and it starts from a young age when girls are dressed in bikinis, even when they are pre-pubescent. We hope this campaign reverses this."
Across Catalonia and the rest of Spain, women have the right to go topless on beaches but local councils decide regulations relating to municipal pools. Privately-owned pools are managed by the owners.
'Nothing else to sort out in Catalonia?'
Last year, Mariona Trabal, co-founder of Mugrons Lliures, or Free Nipples, won a campaign to allow women to go topless at municipal swimming pools in Barcelona, arguing that they should have the same rights as men to bare their chests if they wanted.
However, despite her victory, she said she believed that fewer younger women go topless when they go to the beach.
"Younger women seem more worried about men looking at them when they are on the beach," Ms Trabal, 69, told The Telegraph.
The topless campaign attracted criticism, with Manuel Mendoza tweeting: "In reality is there nothing better to sort out in Catalonia?"
Claudia Gaeta Ruffo wrote on social media: "The Catalan government spends everyone's money on pro-topless campaigns because it thinks I am afraid of my breasts. Let's see if the regional sets an example and shows that he is not afraid of his penis."
Catalonia is governed by a moderate Left-wing Esquerra Republicana party that supports Spain's minority government.
